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  • 51.
    Ahmadivand, Arash
    et al.
    Rice Univ, Dept Elect & Comp Engn, 6100 Main St, Houston, TX 77005 USA.
    Gerislioglu, Burak
    Rice Univ, Dept Phys & Astron, 6100 Main St, Houston, TX 77005 USA.
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Mishra, Yogendra Kumar
    Univ Kiel, Funct Nanomat, Inst Mat Sci, Kaiserstr 2, D-24143 Kiel, Germany.
    Terahertz plasmonics: The rise of toroidal metadevices towards immunobiosensings2020In: Materials Today, ISSN 1369-7021, E-ISSN 1873-4103, Vol. 32, p. 108-130Article, review/survey (Refereed)
    Abstract [en]

    This work reviews fundamentals and the recent state-of-art achievements in the field of plasmonic biosensing based terahertz (THz) spectroscopy. Being nonpoisonous and nondestructive to the human tissues, THz signals offer promising, cost-effective, and real-time biodevices for practical pharmaco-logical applications such as enzyme reaction analysis. Rapid developments in the field of THz plasmonics biosensors and immunosensors have brought many methodologies to employ the resonant subwavelength structures operating based on the fundamental physics of multipoles and asymmetric lineshape resonances. In the ongoing hunt for new and advanced THz plasmonic biosensors, the toroidal metasensors have emerged as excellent alternates and are introduced to be a very promising technology for THz immunosensing applications. Here, we provide examples of recently proposed THz plasmonic metasensors for the detection of thin films, chemical and biological substances. This review allows to compare the performance of various biosensing tools based on THz plasmonic approach and to understand the strategic role of toroidal metasensors in highly accurate and sensitive biosensors instrumentation. The possibility of using THz plasmonic biosensors based on toroidal technology in modern medical and clinical practices has been briefly discussed.

  • 52.
    Ahmadivand, Arash
    et al.
    Rice Univ, Dept Elect & Comp Engn, 6100 Main St, Houston, TX 77005 USA..
    Gerislioglu, Burak
    Rice Univ, Dept Phys & Astron, 6100 Main St, Houston, TX 77005 USA..
    Ahuja, Rajeev
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory. Uppsala Univ, Condensed Matter Theory Grp, Dept Phys & Astron, Box 516, S-75120 Uppsala, Sweden..
    Mishra, Yogendra Kumar
    Univ Southern Denmark, Mads Clausen Inst, NanoSYD, Alsion 2, DK-6400 Sonderborg, Denmark..
    Toroidal Metaphotonics and Metadevices2020In: Laser & Photonics reviews, ISSN 1863-8880, E-ISSN 1863-8899, Vol. 14, no 11, article id 1900326Article, review/survey (Refereed)
    Abstract [en]

    Toroidal moments in artificial media have received growing attention and considered as a promising framework for initiating novel approaches to manage intrinsic radiative losses in nanophotonic and plasmonic systems. In the past decade, there has been substantial attention on the characteristics and excitation methods of toroidal multipoles-in particular, toroidal dipole-in 3D bulk and planar metaplatforms. The remarkable advantages of toroidal resonances have thrust the toroidal metasurface technology from relative anonymity into the limelight, in which researchers have recently centered on developing applied optical and optoelectronic subwavelength devices based on toroidal metaphotonics and metaplasmonics. In this focused contribution, the key principles of 3D and flatland toroidal metastructures are described, and the revolutionary tools that have been implemented based on this topology are briefly highlighted. Infrared photodetectors, immunobiosensors, ultraviolet beam sources, waveguides, and functional modulators are some of the fundamental and latest examples of toroidal metadevices that have been introduced and studied experimentally so far. The possibility of the realization of strong plexciton dynamics and pronounced vacuum Rabi oscillations in toroidal plasmonic metasurfaces are also presented in this review. Ultimate efficient extreme-subwavelength scale devices, such as low-threshold lasers and ultrafast switches, are thus in prospect.

  • 53.
    Ahmed, Jawwad
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Monti, Paolo
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Wosinska, Lena
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Optical Network Laboratory (ON Lab).
    Spadaro, S
    Enhancing restoration performance using service relocation in PCE-based resilient optical clouds2014In: Conference on Optical Fiber Communication, Technical Digest Series, 2014Conference paper (Refereed)
    Abstract [en]

    This paper investigates the benefits of dynamic restoration with service relocation in resilient optical clouds. Results from the proposed optimization model show that service availability can be significantly improved by allowing a few service relocations.

  • 54.
    Ahmed, Rizwan
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Abbas, Shahid
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    Electrical and Optical Characteristics of InP Nanowires based p-i-n Photodetectors2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Photodetectors are a kind of semiconductor devices that convert incoming light to an electrical signal. Photodetectors are classified based on their different structure, fabrication technology, applications and different sensitivity. Infrared photodetectors are widely used in many applications such as night vision, thermal cameras, remote temperature sensing, and medical diagnosis etc.

     

    All detectors have material inside that is sensitive to incoming light. It will absorb the photons and, if the incoming photons have enough energy, electrons will be excited to higher energy levels and if these electrons are free to move, under the effect of an external electric field, a photocurrent is generated.

     

    In this project Fourier Transform Infrared (FT-IR) Spectroscopy is used to investigate a new kind of photodiodes that are based on self-assembled semiconductor nanowires (NWs) which are grown directly on the substrate without any epi-layer. The spectrally resolved photocurrent (at different applied biases) and IV curves (in darkness and illumination) for different temperatures have been studied respectively. Polarization effects (at low and high Temperatures) have been investigated.  The experiments are conducted for different samples with high concentration of NWs as well as with lower concentration of NWs in the temperature range from 78 K (-195ºC) to 300 (27ºC). These photodiodes are designed to work in near infrared (NIR) spectral range.

     

    The results show that the NW photodetectors indeed are promising devices with fairly high break down voltage, change of photocurrent spectra with polarized light, low and constant reverse saturation current (Is). The impact of different polarized light on photocurrent spectra has been investigated and an attempt has been made to clarify the observed double peak of InP photocurrent spectrum. Our investigations also include a comparison to a conventional planar InP p-i-n photodetector.

     

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  • 55.
    Ahufinger, V.
    et al.
    Grup d’Òptica, Departament de Física, Universitat Autònoma de Barcelona, E-08193 Belaterra, Barcelona, Spain;Institut für Theoretische Physik, Universität Hannover, D-30167 Hannover, Germany.
    Sanchez-Palencia, L.
    Institut für Theoretische Physik, Universität Hannover, D-30167 Hannover, Germany;Laboratoire Charles Fabry, Institut d’Optique Théorique et Appliquée, Université Paris-Sud XI, F-91403 Orsay Cedex, France.
    Kantian, A.
    Institut für Theoretische Physik, Universität Hannover, D-30167 Hannover, Germany;Institut für Quantenoptik und Quanteninformation der Österreichischen, Akademie der Wissenschaften, A-6020 Innsbruck, Austria;Institut für Theoretische Physik, Universität Innsbruck, A-6020 Innsbruck, Austria.
    Sanpera, A.
    Institut für Theoretische Physik, Universität Hannover, D-30167 Hannover, Germany;Grup de Física Teòrica, Departament de Física, Universitat Autònoma de Barcelona, E-08193 Belaterra, Barcelona, Spain.
    Lewenstein, M.
    Institut für Theoretische Physik, Universität Hannover, D-30167 Hannover, Germany;Institut de Ciències Fotòniques, E-08034 Barcelona, Spain.
    Disordered ultracold atomic gases in optical lattices: A case study of Fermi-Bose mixtures2005In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 72, no 6Article in journal (Refereed)
    Abstract [en]

    We present a review of properties of ultracold atomic Fermi-Bose mixtures in inhomogeneous and random optical lattices. In the strong interacting limit and at very low temperatures, fermions form, together with bosons or bosonic holes, composite fermions. Composite fermions behave as a spinless interacting Fermi gas, and in the presence of local disorder they interact via random couplings and feel effective random local potential. This opens a wide variety of possibilities of realizing various kinds of ultracold quantum disordered systems. In this paper we review these possibilities, discuss the accessible quantum disordered phases, and methods for their detection. The discussed quantum phases include Fermi glasses, quantum spin glasses, “dirty” superfluids, disordered metallic phases, and phases involving quantum percolation.

  • 56.
    Ahvenniemi, Esko
    et al.
    Aalto Univ, Dept Chem, POB 16100, FI-00076 Espoo, Finland..
    Akbashev, Andrew R.
    Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA..
    Ali, Saima
    Aalto Univ, Sch Chem Technol, Dept Mat Sci & Engn, POB 16200, FI-00076 Aalto, Finland..
    Bechelany, Mikhael
    Univ Montpellier, ENSCM, CNRS, IEM,UMR 5635, Pl Eugene Bataillon, F-34095 Montpellier 5, France..
    Berdova, Maria
    Univ Twente, Ind Focus Grp XUV Opt, NL-7522 ND Enschede, Netherlands..
    Boyadjiev, Stefan
    Bulgarian Acad Sci, Inst Solid State Phys, 72 Tzarigradsko Chaussee Blvd, Sofia 1784, Bulgaria..
    Cameron, David C.
    Masaryk Univ, CEPLANT, Kotlarska 267-2, CS-61137 Brno, Czech Republic..
    Chen, Rong
    Huazhong Univ Sci & Technol, Sch Mech Sci & Engn, Sch Opt & Elect Informat, 1037 Luoyu Rd, Wuhan 430074, Hubei, Peoples R China..
    Chubarov, Mikhail
    Univ Grenoble Alpes, CNRS, SIMAP, F-38000 Grenoble, France..
    Cremers, Veronique
    Univ Ghent, CoCooN, Dept Solid State Sci, Krijgslaan 281-S1, B-9000 Ghent, Belgium..
    Devi, Anjana
    Ruhr Univ Bochum, Inorgan Mat Chem, D-44801 Bochum, Germany..
    Drozd, Viktor
    St Petersburg State Univ, Inst Chem, Univ Skaya Emb 7-9, St Petersburg 199034, Russia..
    Elnikova, Liliya
    Inst Theoret & Expt Phys, Bolshaya Cheremushkinskaya 25, Moscow 117218, Russia..
    Gottardi, Gloria
    Fdn Bruno Kessler, Ctr Mat & Microsyst, I-38123 Trento, Italy..
    Grigoras, Kestutis
    VTT Tech Res Ctr Finland, POB 1000,Tietotie 3, FI-02044 Espoo, Vtt, Finland..
    Hausmann, Dennis M.
    Lam Res Corp, Tualatin, OR 97062 USA..
    Hwang, Cheol Seong
    Seoul Natl Univ, Dept Mat Sci & Engn, Coll Engn, Seoul 08826, South Korea.;Seoul Natl Univ, Interuniv Semicond Res Ctr, Coll Engn, Seoul 08826, South Korea..
    Jen, Shih-Hui
    Globalfoundries, Albany, NY 12203 USA..
    Kallio, Tanja
    Aalto Univ, Sch Chem Engn, Dept Chem, POB 16100, FI-00076 Aalto, Finland..
    Kanervo, Jaana
    Aalto Univ, Sch Chem Engn, Dept Chem, POB 16100, FI-00076 Aalto, Finland.;Abo Akad Univ, FI-20500 Turku, Finland..
    Khmelnitskiy, Ivan
    St Petersburg Electrotech Univ LETI, Res & Educ Ctr Nanotechnol, Ul Prof Popova 5, St Petersburg 197376, Russia..
    Kim, Do Han
    MIT, Dept Chem Engn, 77 Massachusetts Ave, Cambridge, MA 02139 USA..
    Klibanov, Lev
    Techinsights, 3000 Solandt Rd, Ottawa, ON K2K2X2, Canada..
    Koshtyal, Yury
    Ioffe Inst, Lab Lithium Ion Technol, 26 Politekhnicheskaya, St Petersburg 194021, Russia..
    Krause, A. Outi I.
    Aalto Univ, Sch Chem Technol, Dept Mat Sci & Engn, POB 16200, FI-00076 Aalto, Finland..
    Kuhs, Jakob
    Univ Ghent, CoCooN, Dept Solid State Sci, Krijgslaan 281-S1, B-9000 Ghent, Belgium..
    Kaerkkaenen, Irina
    Sentech Instruments GmbH, Schwarzschildstr 2, D-12489 Berlin, Germany..
    Kaariainen, Marja-Leena
    NovaldMed Ltd Oy, Telkantie 5, FI-82500 Kitee, Finland..
    Kaariainen, Tommi
    NovaldMed Ltd Oy, Telkantie 5, FI-82500 Kitee, Finland.;Univ Helsinki, Inorgan Chem Lab, POB 55,AI Virtasen Aukio 1, FI-00014 Helsinki, Finland..
    Lamagna, Luca
    STMicroelectronics, Via C Olivetti 2, I-20864 Agrate Brianza, MB, Italy..
    Lapicki, Adam A.
    Seagate Technol Ireland, 1 Disc Dr, Derry BT48 7BD, North Ireland..
    Leskela, Markku
    Univ Helsinki, Dept Chem, POB 55, FI-00014 Helsinki, Finland..
    Lipsanen, Harri
    Aalto Univ, Dept Micro & Nanosci, Tietotie 3, Espoo 02150, Finland..
    Lyytinen, Jussi
    Aalto Univ, Sch Chem Technol, Dept Mat Sci & Engn, POB 16200, FI-00076 Aalto, Finland..
    Malkov, Anatoly
    Tech Univ, St Petersburg State Inst Technol, Dept Chem Nanotechnol & Mat Elect, 26 Moskovsky Prosp, St Petersburg 190013, Russia..
    Malygin, Anatoly
    Tech Univ, St Petersburg State Inst Technol, Dept Chem Nanotechnol & Mat Elect, 26 Moskovsky Prosp, St Petersburg 190013, Russia..
    Mennad, Abdelkader
    CDER, UDES, RN 11 BP 386 Bou Ismail, Tipasa 42415, Algeria..
    Militzer, Christian
    Tech Univ Chemnitz, Inst Chem, Phys Chem, Str Nationen 62, D-09111 Chemnitz, Germany..
    Molarius, Jyrki
    Summa Semicond Oy, PL 11, Espoo 02131, Finland..
    Norek, Malgorzata
    Mil Univ Technol, Fac Adv Technol & Chem, Dept Adv Mat & Technol, Str Kaliskiego 2, PL-00908 Warsaw, Poland..
    Ozgit-Akgun, Cagla
    ASELSAN Inc, Microelect Guidance & Electroopt Business Sect, TR-06750 Ankara, Turkey..
    Panov, Mikhail
    St Petersburg Electrotech Univ LETI, Ctr Microtechnol & Diagnost, Ul Prof Popova 5, St Petersburg 197376, Russia..
    Pedersen, Henrik
    Linkoping Univ, Dept Phys Chem & Biol, SE-58183 Linkoping, Sweden..
    Piallat, Fabien
    KOBUS, F-38330 Montbonnot St Martin, France..
    Popov, Georgi
    Univ Helsinki, Dept Chem, POB 55, FI-00014 Helsinki, Finland..
    Puurunen, Riikka L.
    VTT Tech Res Ctr Finland, POB 1000,Tietotie 3, FI-02044 Espoo, Vtt, Finland..
    Rampelberg, Geert
    Univ Ghent, CoCooN, Dept Solid State Sci, Krijgslaan 281-S1, B-9000 Ghent, Belgium..
    Ras, Robin H. A.
    Rauwel, Erwan
    Tallinn Univ Technol, Tartu Coll, Puiestee 78, EE-51008 Tartu, Estonia..
    Roozeboom, Fred
    Eindhoven Univ Technol, Dept Appl Phys, Grp Plasma & Mat Proc, POB 513, NL-5600 MB Eindhoven, Netherlands.;TNO, High Tech Campus 21, NL-5656 AE Eindhoven, Netherlands..
    Sajavaara, Timo
    Univ Jyvaskyla, Dept Phys, POB 35, Jyvaskyla 40014, Finland..
    Salami, Hossein
    Univ Maryland, Dept Chem & Biomol Engn, College Pk, MD 20742 USA..
    Savin, Hele
    Aalto Univ, Dept Micro & Nanosci, Tietotie 3, Espoo 02150, Finland..
    Schneider, Nathanaelle
    IRDEP CNRS, 6 Quai Watier, F-78401 Chatou, France.;IPVF, 8 Rue Renaissance, F-92160 Antony, France..
    Seidel, Thomas E.
    Seitek50, POB 350238, Palm Coast, FL 32135 USA..
    Sundqvist, Jonas
    Fraunhofer Inst Ceram Technol & Syst IKTS, Syst Integrat & Technol Transfer, Winterbergstr 28, D-01277 Dresden, Germany..
    Suyatin, Dmitry B.
    Lund Univ, Div Solid State Phys, Box 118, SE-22100 Lund, Sweden.;Lund Univ, NanoLund, Box 118, SE-22100 Lund, Sweden..
    Törndahl, Tobias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    van Ommen, J. Ruud
    Delft Univ Technol, Dept Chem Engn, Van der Maasweg 9, NL-2629 HZ Delft, Netherlands..
    Wiemer, Claudia
    CNR, IMM, Lab MDM, Via C Olivetti 2, I-20864 Agrate Brianza, MB, Italy..
    Ylivaara, Oili M. E.
    VTT Tech Res Ctr Finland, POB 1000,Tietotie 3, FI-02044 Espoo, Vtt, Finland..
    Yurkevich, Oksana
    Immanuel Kant Balt Fed Univ, Res & Educ Ctr Funct Nanomat, A Nevskogo 14, Kaliningrad 236041, Russia..
    Recommended reading list of early publications on atomic layer deposition-Outcome of the "Virtual Project on the History of ALD"2017In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 35, no 1, article id 010801Article, review/survey (Refereed)
    Abstract [en]

    Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency.

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  • 57. Ai, Yue-jie
    et al.
    Tian, Guangjun
    Liao, Rong-zhen
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhang, Qiong
    Fang, Wei-hai
    Luo, Yi
    Intrinsic Property of Flavin Mononucleotide Controls its Optical Spectra in Three Redox States2011In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 12, no 16, p. 2899-2902Article in journal (Refereed)
  • 58.
    Akan, Rabia
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Parfeniukas, Karolis
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Vogt, Carmen
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics. KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova.
    Toprak, Muhammet
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Vogt, Ulrich
    KTH, School of Engineering Sciences (SCI), Applied Physics, Biomedical and X-ray Physics.
    Investigation of Metal-Assisted Chemical Etching for Fabrication of Silicon-Based X-Ray Zone Plates2018In: Microscopy and Microanalysis, ISSN 1431-9276, E-ISSN 1435-8115Article in journal (Refereed)
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  • 59.
    Akbari-Saatlu, Mehdi
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Procek, Marcin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Silesian University of Technology, Poland.
    Mattsson, Claes
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Thungström, Göran
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design.
    Törndahl, T.
    Li, B.
    Su, J.
    Xiong, W.
    Radamson, Henry H.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Electronics Design. Guangdong Greater Bay Area Institute of Integrated Circuit and System, Guangzhou, China; Chinese Academy of Sciences, Beijing, China .
    Nanometer-Thick ZnO/SnO2Heterostructures Grown on Alumina for H2S Sensing2022In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 5, no 5, p. 6954-6963Article in journal (Refereed)
    Abstract [en]

    Designing heterostructure materials at the nanoscale is a well-known method to enhance gas sensing performance. In this study, a mixed solution of zinc chloride and tin (II) chloride dihydrate, dissolved in ethanol solvent, was used as the initial precursor for depositing the sensing layer on alumina substrates using the ultrasonic spray pyrolysis (USP) method. Several ZnO/SnO2 heterostructures were grown by applying different ratios in the initial precursors. These heterostructures were used as active materials for the sensing of H2S gas molecules. The results revealed that an increase in the zinc chloride in the USP precursor alters the H2S sensitivity of the sensor. The optimal working temperature was found to be 450 °C. The sensor, containing 5:1 (ZnCl2: SnCl2·2H2O) ratio in the USP precursor, demonstrates a higher response than the pure SnO2 (∼95 times) sample and other heterostructures. Later, the selectivity of the ZnO/SnO2 heterostructures toward 5 ppm NO2, 200 ppm methanol, and 100 ppm of CH4, acetone, and ethanol was also examined. The gas sensing mechanism of the ZnO/SnO2 was analyzed and the remarkably enhanced gas-sensing performance was mainly attributed to the heterostructure formation between ZnO and SnO2. The synthesized materials were also analyzed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, and X-ray photoelectron spectra to investigate the material distribution, grain size, and material quality of ZnO/SnO2 heterostructures. 

  • 60.
    Akerlind, C.
    et al.
    Swedish Def Res Agcy FOI, Div Electro Opt Systmes, SE-58111 Linkoping, Sweden.
    Hallberg, T.
    Swedish Def Res Agcy FOI, Div Electro Opt Systmes, SE-58111 Linkoping, Sweden.
    Järrendahl, Kenneth
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Optical Studies of White Organic Materials for Camouflage Applications in Arctic Environments2022In: TARGET AND BACKGROUND SIGNATURES VIII, SPIE-INT SOC OPTICAL ENGINEERING , 2022, Vol. 12270, article id 122700DConference paper (Refereed)
    Abstract [en]

    Important properties for camouflage materials can be summarized in six criteria: (1) spectrally selective reflectance, (2) low gloss, (3) low degree of polarization, (4) low infrared emissivity, (5) non-destructive effect on radar properties and (6) color adaptivity. We have studied a collection of natural materials for potential use as camouflage surfaces for the arctic region. The four first camouflage criteria are analyzed using spectrometry, scatterometry and spectroscopic ellipsometry techniques. The materials involved in the study are diffuse white nature-inspired surfaces: Cuticles of the beetle Cyphochilus insulanus, and foams of freeze-casted cellulose nanofibrils. We present data that partly fulfills the addressed camouflage criteria. An adequate reflectance is achieved in the spectral range of 400 - 1600 nm for both samples. Scattering data show that near-Lambertian properties are achieved at 633 nm for both surfaces but at 1550 nm for only the beetle cuticle. The degree of polarization is low for unpolarized light incident near the surface normal for both surfaces.

  • 61.
    Ako, Thomas
    et al.
    Laboratory of Photonic and Microwave Engineering, School of Information and Communication Technology, Royal Insitute of Technology, Electrum 229, Kista, Sweden.
    Yan, Min
    Laboratory of Photonic and Microwave Engineering, School of Information and Communication Technology, Royal Insitute of Technology, Electrum 229, Kista, Sweden.
    Qiu, Min
    Laboratory of Photonic and Microwave Engineering, School of Information and Communication Technology, Royal Insitute of Technology, Electrum 229, Kista, Sweden.
    Design of invisibility cloaks with an open tunnel2010In: Optics Express, E-ISSN 1094-4087, Vol. 18, no 26, p. 27060-27066Article in journal (Refereed)
    Abstract [en]

    In this paper we apply the methodology of transformation optics for design of a novel invisibility cloak which can possess an open tunnel. Such a cloak facilitates the insertion (retrieval) of matter into (from) the cloak’s interior without significantly affecting the cloak’s performance, overcoming the matter exchange bottleneck inherent to most previously proposed cloak designs. We achieve this by applying a transformation which expands a point at the origin in electromagnetic space to a finite area in physical space in a highly anisotropic manner. The invisibility performance of the proposed cloak is verified by using full-wave finite-element simulations.

  • 62.
    Ako, Thomas
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics.
    Yan, Min
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Qiu, Min
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Design of invisibility cloaks with an open tunnel2010In: Optics Express, E-ISSN 1094-4087, Vol. 18, no 26, p. 27060-27066Article in journal (Refereed)
    Abstract [en]

    In this paper we apply the methodology of transformation optics for design of a novel invisibility cloak which can possess an open tunnel. Such a cloak facilitates the insertion (retrieval) of matter into (from) the cloak's interior without significantly affecting the cloak's performance, overcoming the matter exchange bottleneck inherent to most previously proposed cloak designs. We achieve this by applying a transformation which expands a point at the origin in electromagnetic space to a finite area in physical space in a highly anisotropic manner. The invisibility performance of the proposed cloak is verified by using full-wave finite-element simulations. (C) 2010 Optical Society of America

  • 63. Akram, N. M.
    et al.
    Schatz, Richard
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Marcinkevicius, Saulius
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Kjebon, Olle
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Berggren, Jesper
    KTH, School of Information and Communication Technology (ICT), Integrated Devices and Circuits.
    Experimental evaluation of carrier transport, gain, T0 and chirp of 1.55 mu;m MQW structures with different barrier compositions2005In: Optical Communication, 2005. ECOC 2005. 31st European Conference on, 2005, Vol. 2, p. 297-298Conference paper (Refereed)
    Abstract [en]

    Direct carrier transport measurements were performed for different InGaAsP/InGaAlAs MQW test structures. Shallow InGaAlAs barrier QW showed faster carrier transport. Semi-insulating regrown FP lasers with InGaAlAs barrier QW showed improved high temperature operation, modal gain, differential modal gain and chirp.

  • 64.
    Akram, Nadeem
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Kjebon, Olle
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Chacinski, Marek
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP. KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Schatz, Richard
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP. KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Berggren, Jesper
    KTH, School of Information and Communication Technology (ICT), Material Physics, Semiconductor Materials, HMA.
    Olsson, Fredrik
    KTH, School of Information and Communication Technology (ICT), Material Physics, Semiconductor Materials, HMA.
    Lourdudoss, Sebastian
    KTH, School of Information and Communication Technology (ICT), Material Physics, Semiconductor Materials, HMA.
    Berrier, Audrey
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Applied Physics, MAP.
    Experimental characterization of high-speed 1.55 mu m buried heterostructure InGaAsP/InGaAlAs quantum-well lasers2009In: Journal of the Optical Society of America. B, Optical physics, ISSN 0740-3224, E-ISSN 1520-8540, Vol. 26, no 2, p. 318-327Article in journal (Refereed)
    Abstract [en]

    Detailed experimental characterization is performed for 1550 nm semi-insulating regrown buried heterostructure Fabry-Perot (FP) lasers having 20 InGaAsP/InGaAlAs strain-balanced quantum wells (QWs) in the active region. Light-current-voltage performance, electrical impedance, small-signal response below and above threshold, amplified spontaneous emission spectrum below threshold and relative intensity noise spectrum are measured. Different laser parameters such as external differential quantum efficiency eta(d), background optical loss alpha(i), K-factor, D-factor, characteristic temperature T-0, differential gain dg/dn, gain-compression factor epsilon, carrier density versus current, differential carrier lifetime tau(d), optical gain spectrum below threshold, and chirp parameter alpha are extracted from these measurements. The FP lasers exhibited a high T-0 (78-86.5 degrees C) and very high-resonance frequency (23.7 GHz). The results indicate that appropriately designed lasers having a large number of InGaAsP well/InGaAlAs barrier QWs with shallow valence-band discontinuity can be useful for un-cooled high-speed direct-modulated laser applications.

  • 65.
    Akram, Nadeem
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Kjebon, Olle
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Chacinski, Marek
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Schatz, Richard
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Photonics.
    Berggren, Jesper
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Olsson, Fredrik
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Lourdudoss, Sebastian
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Berrier, Audrey
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    High-Speed Performance of 1.55 µm Buried Hetero-Structure Lasers with 20 InGaAsP/InGaAlAs Quantum-Wells2006In: 2006 European Conference on Optical Communications Proceedings, ECOC 2006, IEEE , 2006, p. 1-2Conference paper (Refereed)
    Abstract [en]

    1550 nm re-grown FP lasers having 20 InGaAsP/InGaAlAs strain-balanced QWs exhibit low threshold current density, high T0 (78.0 #x000B0;C) and high resonance frequency (24 GHz) indicating that a large number of shallow barrier QWs are attractive for un-cooled high-speed direct-modulation applications.

  • 66.
    Akram, Nadeem
    et al.
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Silfvenius, Christofer
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Berggren, Jesper
    KTH, School of Information and Communication Technology (ICT), Material Physics, Semiconductor Materials, HMA.
    Kjebon, Olle
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Schatz, Richard
    KTH, School of Information and Communication Technology (ICT), Microelectronics and Information Technology, IMIT.
    Design optimization of InGaAsP-InGaAlAs 1.55 mu;m strain-compensated MQW lasers for direct modulation applications2004In: Indium Phosphide and Related Materials, 2004. 16th IPRM. 2004 International Conference on, IEEE , 2004, p. 418-421Conference paper (Refereed)
    Abstract [en]

    A comprehensive simulation study of InGaAsP (well)/InGaAlAs(barrier) 1.55 mu;m strain-compensated MQW lasers is presented. For MQWs, a uniform vertical distribution of holes is achieved due to a reduced effective hole confinement energy by optimizing the bandgap and strain of the barriers and p-doping in the active region. Some preliminary results are also presented for the manufactured lasers using these QWs indicating a good material platform.

  • 67.
    Akser, Marielle
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Detections of nuclear explosions by triple coincidence2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When a nuclear explosion occurs certain radionuclides are emitted, notably xenon. Due to the fact that xenon is a noble gas, it is hard to contain and can therefore be detected far from the explosion site. There are four isotopes of xenon that are of interest in the detection of a nuclear explosion: 131mXe, 133mXe, 133Xe and 135Xe. By constantly measuring the amount of these isotopes in the air, changes in the concentration in an indication that a nuclear explosion has occurred. In this thesis a detector was modelled in GEANT4 and focuses on one kind of noble gas detector: SAUNA - the Swedish Automatic Unit for Noble gas Acquisition. SAUNA uses the coincidence technique in order to determine the concentration of xenon there is in the air. By using the coincidence technique, it is possible to reduce the impact of the background radiation and therefore increase the efficiency of the detector. 133Xe has a coincidence when it first undergoes beta decay, with an endpoint energy of 346 keV, and then emits a 80 keV gamma particle. 135Xe has also a dual coincidence, a beta decay with an endpoint energy of 910 keV together with a 250 keV gamma-ray. However both these isotopes have a triple coincidence decay that also can be exploited: for 133Xe, a beta particle with endpoint energy of 346 keV, a 30 keV X-ray and a 45 keV conversion electron, while for 135Xe there is instead of the gamma particle a 30 keV X-ray and a 214keV conversion electron that can be emitted together with the beta particle. The 30 keV X-ray together with the beta particle for 133Xe can also be used as a dual coincidence, in that case the conversion electron is ignored. For 133Xe, when a beta particle, a 45 keV conversion electron, and a 30 keV X-ray are emitted, the model was able to detect all three particles in 69.2% ± 0.1 of the cases. However, when only the particles with a detected energy within a 5 keV interval of their generated energies are considered to be in coincidence, then for 133Xe triple coincidence occurs in 22.9% ± 0.2 of the cases. For 135Xe the model was able to detect the triple coincidence (between a beta, 214 keV CE and 30 keV X-ray) in 63.5% ± 0.1 of the cases. This work shows that adding another particle in a coincidence reduces the chance to detect the coincidence. The positive effect of adding another particle in a coincidence is that the minimum detectable concentration of xenon should be smaller. The goal for future detectors should be to make it possible for the detector to take advantage of the triple coincidences but at the same time be also able to use the dual coincidences.

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  • 68. Aktas, Ozan
    et al.
    Ren, H.
    Runge, A. F. J.
    Peacock, A. C.
    Hawkins, T.
    Ballato, J.
    Gibson, Ursula J.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Interfacing telecom fibers and silicon core fibers with nano-spikes for in-fiber silicon devices2018In: 2018 Optical Fiber Communications Conference and Exposition, OFC 2018 - Proceedings, Institute of Electrical and Electronics Engineers Inc. (IEEE) , 2018, p. 1-3Conference paper (Refereed)
    Abstract [en]

    We report fabrication of tapered silicon core fibers with nano-spikes enabling efficient optical coupling into the core, as well as their seamless integration with single mode fibers. A proof-of-concept integrated in-fiber silicon device is demonstrated.

  • 69. Aladi, M.
    et al.
    Bolla, R.
    Cardenas, D. E.
    Veisz, László
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Foldes, I. B.
    Cluster size distributions in gas jets for different nozzle geometries2017In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 12, article id C06020Article in journal (Refereed)
    Abstract [en]

    Cluster size distributions were investigated in case of different nozzle geometries in argon and xenon using Rayleigh scattering diagnostics. Different nozzle geometries result in different behaviour, therefore both spatial- and temporal cluster size distributions were studied to obtain a well-characterized cluster target. It is shown that the generally used Hagena scaling can result in a significant deviation from the observed data and the behaviour cannot be described by a single material condensation parameter. The results along with the nanoplasma model applied to the data of previous high harmonic generation experiments allow the independent measurement of cluster size and cluster density.

  • 70. Alagia, M
    et al.
    Coreno, M
    Farrokhpour, H
    Franceschi, P
    Mihelic, A
    Moise, A
    Omidyan, R
    Prince, K C
    Richter, R
    Söderström, J
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Stranges, S
    Tabrizchi, M
    Åœitnik, M
    Angular effects in autoionization of 3 P doubly excited states in He2009In: Journal of Physics: Conference Series, Vol. 194Article in journal (Refereed)
    Abstract [en]

    The first members of dipole allowed 3 P o doubly excited series in helium have been observed in resonant photoexcitation of 1 s 2 s 3 S e metastable atoms. A good agreement measured relative photoionization cross sections is achieved when theory includes the radiation damping and, also important, the effects of spin-orbit multiplet splitting on electron angular distribution.

  • 71. Alagia, M
    et al.
    Coreno, M
    Farrokhpour, H
    Franceschi, P
    Mihelič, A
    Moise, A
    Omidyan, R
    Prince, K C
    Richter, R
    Söderström, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
    Stranges, S
    Tabrizchi, M
    Åœitnik, M
    Angular effects in autoionization of 3 P doubly excited states in He2009In: Journal of Physics: Conference Series, Vol. 194, no 2Article in journal (Refereed)
    Abstract [en]

    The first members of dipole allowed 3 P o doubly excited series in helium have been observed in resonant photoexcitation of 1 s 2 s 3 S e metastable atoms. A good agreement measured relative photoionization cross sections is achieved when theory includes the radiation damping and, also important, the effects of spin-orbit multiplet splitting on electron angular distribution.

  • 72.
    Alarcon, Alvaro
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Argillander, Joakim
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Spegel-Lexne, Daniel
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Xavier, Guilherme B.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Quantum Random Number Generation Based on Spatial Modal Superposition over Few-Mode-Fibers2022In: Frontiers in Optics + Laser Science 2022 (FIO, LS), Optica Publishing Group , 2022Conference paper (Refereed)
    Abstract [en]

    A quantum random number generator based on few-mode fiber technology is presented. The randomness originates from measurements of spatial modal quantum superpositions of the LP11a and LP11b modes. The generated sequences have passed NIST tests.

  • 73.
    Alarcon, Alvaro
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Argillander, Joakim
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Xavier, Guilherme B.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Creating Spatial States of Light for Quantum Information with Photonic Lanterns2021In: Applied Industrial Optics 2021 / [ed] G. Miller, A. Smith, I. Capraro, and J. Majors, Optical Society of America, 2021, article id W2A.2Conference paper (Refereed)
    Abstract [en]

    We demonstrate an all-fiber platform for the generation and detection of spatial photonic states where combinations of LP01, LP11a and LP11b modes are used. This scheme can be employed for quantum communication applications.

  • 74.
    Alarcon, Alvaro
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Gomez, Santiago
    Univ Concepcion, Chile; Univ Bio Bio, Chile.
    Spegel-Lexne, Daniel
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Argillander, Joakim
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Carine, Jaime
    Univ Catolica Santisima Concepcion, Chile.
    Canas, Gustavo
    Univ Bio Bio, Chile.
    Lima, Gustavo
    Univ Concepcion, Chile; Univ Concepcion, Chile.
    Xavier, Guilherme B
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    All-in-Fiber Dynamically Reconfigurable Orbital Angular Momentum Mode Sorting2023In: ACS Photonics, E-ISSN 2330-4022, Vol. 10, no 10, p. 3700-3707Article in journal (Refereed)
    Abstract [en]

    The orbital angular momentum (OAM) spatial degree of freedom of light has been widely explored in many applications, including telecommunications, quantum information, and light-based micromanipulation. The ability to separate and distinguish between the different transverse spatial modes is called mode sorting or mode demultiplexing, and it is essential to recover the encoded information in such applications. An ideal d mode sorter should be able to faithfully distinguish between the different d spatial modes, with minimal losses, and have d outputs and fast response times. All previous mode sorters rely on bulk optical elements, such as spatial light modulators, which cannot be quickly tuned and have additional losses if they are to be integrated with optical fiber systems. Here, we propose and experimentally demonstrate, to the best of our knowledge, the first all-in-fiber method for OAM mode sorting with ultrafast dynamic reconfigurability. Our scheme first decomposes the OAM mode in-fiber-optical linearly polarized (LP) modes and then interferometrically recombines them to determine the topological charge, thus correctly sorting the OAM mode. In addition, our setup can also be used to perform ultrafast routing of the OAM modes. These results show a novel and fiber-integrated form of optical spatial mode sorting that can be readily used for many new applications in classical and quantum information processing.

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  • 75.
    Alarcon, Alvaro
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Xavier, Guilherme B.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    A few-mode fiber Mach-Zehnder interferometer for quantum communication applications2020In: Frontiers in Optics / Laser Science / [ed] B. Lee, C. Mazzali, K. Corwin, and R. Jason Jones, Optical Society of America, 2020, article id LM1F.6Conference paper (Refereed)
    Abstract [en]

    We show that telecom few-mode fiber Mach-Zehnder interferometers can be used for quantum communication protocols where the LP01 and LP11a modes are employed to encode spatial qubits.

  • 76.
    Al-attar, Nebras
    et al.
    School of biosystems and food Engineering, University of Technology, Baghdad, 10066, Iraq; Laser and Optoelectronics Engineering Department, University of Technology, Baghdad, 10066, Iraq.
    Al-Shammari, Rusul M.
    School of Physics, University College Dublin Belfield, 7 Dublin, D04 N2E5, Ireland; Conway Institute of Biomolecular and Biomedical Research, University College Dublin Belfield, 7 Dublin, D04 N2E5, Ireland.
    Manzo, Michele
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum Electronics and Quantum Optics, QEO.
    Gallo, Katia
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum Electronics and Quantum Optics, QEO.
    Rodriguez, Brian J.
    School of Physics, University College Dublin Belfield, 7 Dublin, D04 N2E5, Ireland; Conway Institute of Biomolecular and Biomedical Research, University College Dublin Belfield, 7 Dublin, D04 N2E5, Ireland.
    Rice, James H.
    School of Physics, University College Dublin Belfield, 7 Dublin, D04 N2E5, Ireland.
    Wide-field surface-enhanced Raman scattering from ferroelectrically defined Au nanoparticle microarrays for optical sensing2018In: Proceedings CLEO: Applications and Technology 2018, Optica Publishing Group , 2018Conference paper (Refereed)
    Abstract [en]

    The acquisition-time in optical sensors using SERS is vital value. Wide-field SERS is used to perform high-density of hot-spots of GNPs photodeposition on a periodically-protonexchanged- LiNbO3 which, leads to increase the sensitivity at ultralow probe concentrations.

  • 77.
    Alay-e-Abbas, Syed Muhammad
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Computational Materials Modeling Laboratory, Department of Physics, Government College University, Faisalabad, 38040, Pakistan.
    Abbas, Ghulam
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Zulfiqar, Waqas
    Computational Materials Modeling Laboratory, Department of Physics, Government College University, Faisalabad, 38040, Pakistan; Department of Energy Conversion and Storage, Technical University of Denmark, 2800, Kgs. Lyngby, Denmark.
    Sajjad, Muhammad
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science. Department of Physics, Khalifa University of Science and Technology, Abu Dhabi, 127788, United Arab Emirates.
    Singh, Nirpendra
    Department of Physics, Khalifa University of Science and Technology, Abu Dhabi, 127788, United Arab Emirates; Center for Catalysis and Separation (CeCaS), Khalifa University of Science and Technology, Abu Dhabi, 127788, United Arab Emirates.
    Larsson, J. Andreas
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Structure inversion asymmetry enhanced electronic structure and electrical transport in 2D A3SnO (A = Ca, Sr, and Ba) anti-perovskite monolayers2023In: Nano Reseach, ISSN 1998-0124, E-ISSN 1998-0000, Vol. 16, no 1, p. 1779-1791Article in journal (Refereed)
    Abstract [en]

    Anti-perovskites A3SnO (A = Ca, Sr, and Ba) are an important class of materials due to the emergence of Dirac cones and tiny mass gaps in their band structures originating from an intricate interplay of crystal symmetry, spin-orbit coupling, and band overlap. This provides an exciting playground for modulating their electronic properties in the two-dimensional (2D) limit. Herein, we employ first-principles density functional theory (DFT) calculations by combining dispersion-corrected SCAN + rVV10 and mBJ functionals for a comprehensive side-by-side comparison of the structural, thermodynamic, dynamical, mechanical, electronic, and thermoelectric properties of bulk and monolayer (one unit cell thick) A3SnO anti-perovskites. Our results show that 2D monolayers derived from bulk A3SnO anti-perovskites are structurally and energetically stable. Moreover, Rashba-type splitting in the electronic structure of Ca3SnO and Sr3SnO monolayers is observed owing to strong spin-orbit coupling and inversion asymmetry. On the other hand, monolayer Ba3SnO exhibits Dirac cone at the high-symmetry Γ point due to the domination of band overlap. Based on the predicted electronic transport properties, it is shown that inversion asymmetry plays an essential character such that the monolayers Ca3SnO and Sr3SnO outperform thermoelectric performance of their bulk counterparts.

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  • 78.
    Albert, Damien
    et al.
    Univ Grenoble Alpes, CNRS, OSUG, Unite Mixte Rech 832, F-38000 Grenoble, France..
    Antony, Bobby K.
    Indian Sch Mines, Indian Inst Technol, Dhanbad 826004, Bihar, India..
    Ba, Yaye Awa
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Babikov, Yuri L.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia.;Tomsk State Univ, Phys Dept, Lab Quantum Mech & Radiat Transfer QUAMER, Tomsk 634050, Russia..
    Bollard, Philippe
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Boudon, Vincent
    Univ Bourgogne Franche Comte, Lab Interdisciplinaire Carnot Bourgogne, CNRS, UMR 6303, 9 Ave Alain Savary,BP 47 870, F-21078 Dijon, France..
    Delahaye, Franck
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Del Zanna, Giulio
    DAMTP, Ctr Math Sci, Wilberforce Rd, Cambridge CB3 0WA, England..
    Dimitrijevic, Milan S.
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France.;Astron Observ, Volgina 7, Belgrade 11060, Serbia..
    Drouin, Brian J.
    CALTECH, Jet Prop Lab, 4800 Oak Grove Dr, Pasadena, CA 91109 USA..
    Dubernet, Marie-Lise
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Duensing, Felix
    Univ Innsbruck, Inst Ion Phys & Appl Phys, Technikerstr 25-3, A-6020 Innsbruck, Austria..
    Emoto, Masahiko
    Natl Inst Nat Sci, Natl Inst Fus Sci, Toki, Gifu 5095292, Japan..
    Endres, Christian P.
    Max Planck Inst Extraterr Phys, Giessenbachstr, D-85748 Garching, Germany..
    Fazliev, Alexandr Z.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Glorian, Jean-Michel
    Univ Toulouse UPS, Inst Rech Astrophys & Planetol, CNRS, CNES, 9 Av Colonel Roche, F-31028 Toulouse 4, France..
    Gordon, Iouli E.
    Ctr Astrophys Harvard & Smithsonian, Atom & Mol Phys Div, MS50,60 Garden St, Cambridge, MA 02138 USA..
    Gratier, Pierre
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Hill, Christian
    Vienna Int Ctr, Div Phys & Chem Sci, Nucl Data Sect, Int Atom Energy Agcy IAEA, A-1400 Vienna, Austria..
    Jevremovic, Darko
    Astron Observ, Volgina 7, Belgrade 11060, Serbia..
    Joblin, Christine
    Univ Toulouse UPS, Inst Rech Astrophys & Planetol, CNRS, CNES, 9 Av Colonel Roche, F-31028 Toulouse 4, France..
    Kwon, Duck-Hee
    Korea Atom Energy Res Inst, Nucl Data Ctr, Daejeon 34057, South Korea..
    Kochanov, Roman V.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia.;Tomsk State Univ, Phys Dept, Lab Quantum Mech & Radiat Transfer QUAMER, Tomsk 634050, Russia..
    Krishnakumar, Erumathadathil
    Raman Res Inst, CV Raman Ave, Bangalore 560080, Karnataka, India..
    Leto, Giuseppe
    INAF Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Loboda, Petr A.
    All Russian Inst Tech Phys RFNC VNIITF, Russian Fed Nucl Ctr, Snezhinsk 456770, Russia.;Natl Res Nucl Univ, Moscow Engn Phys Inst MEPhI, Moscow 115409, Russia..
    Lukashevskaya, Anastasiya A.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Lyulin, Oleg M.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Marinkovic, Bratislav P.
    Univ Belgrade, Inst Phys Belgrade, POB 57, Belgrade 11001, Serbia..
    Markwick, Andrew
    Univ Manchester, Sch Phys & Astron, Jodrell Bank Ctr Astrophys, Oxford Rd, Manchester M13 9PL, Lancs, England..
    Marquart, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Mason, Nigel J.
    Univ Kent, Sch Phys Sci, Ingram Bldg, Canterbury CT2 7NH, Kent, England..
    Mendoza, Claudio
    Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA..
    Millar, Tom J.
    Queens Univ Belfast, Sch Math & Phys, Univ Rd, Belfast BT7 1NN, Antrim, North Ireland..
    Moreau, Nicolas
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Morozov, Serguei V.
    All Russian Inst Tech Phys RFNC VNIITF, Russian Fed Nucl Ctr, Snezhinsk 456770, Russia..
    Moeller, Thomas
    Univ Cologne, Phys Inst 1, Zulpicher Str 77, D-50937 Cologne, Germany..
    Mueller, Holger S. P.
    Univ Cologne, Phys Inst 1, Zulpicher Str 77, D-50937 Cologne, Germany..
    Mulas, Giacomo
    Univ Toulouse UPS, Inst Rech Astrophys & Planetol, CNRS, CNES, 9 Av Colonel Roche, F-31028 Toulouse 4, France.;Osservatorio Astron Cagliari, Ist Nazl AstroFis, Via Sci 5, I-09047 Selargius, CA, Italy..
    Murakami, Izumi
    Natl Inst Nat Sci, Natl Inst Fus Sci, Toki, Gifu 5095292, Japan.;Grad Univ Adv Studies, Dept Fus Sci, SOKENDAI, Toki, Gifu 5095292, Japan..
    Pakhomov, Yury
    Russian Acad Sci, Inst Astron, Pyatnitskaya 48, Moscow 119017, Russia..
    Palmeri, Patrick
    Univ Mons, Phys Atom & Astrophys, B-7000 Mons, Belgium..
    Penguen, Julien
    Univ La Rochelle, Observ Aquitain Sci Univers, Univ Bordeaux, POREA,CNRS,IRSTEA, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Perevalov, Valery I.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Postler, Johannes
    Univ Innsbruck, Inst Ion Phys & Appl Phys, Technikerstr 25-3, A-6020 Innsbruck, Austria..
    Privezentsev, Alexei I.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Quinet, Pascal
    Univ Mons, Phys Atom & Astrophys, B-7000 Mons, Belgium.;Univ Liege, IPNAS, B-4000 Liege, Belgium..
    Ralchenko, Yuri
    Natl Inst Stand & Technol, Atom Spect Grp, Gaithersburg, MD 20899 USA..
    Rhee, Yong-Joo
    Inst Basic Sci, Ctr Relativist Laser Sci, Gwang Ju 61005, South Korea..
    Richard, Cyril
    Univ Bourgogne Franche Comte, Lab Interdisciplinaire Carnot Bourgogne, CNRS, UMR 6303, 9 Ave Alain Savary,BP 47 870, F-21078 Dijon, France..
    Rixon, Guy
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Rothman, Laurence S.
    Ctr Astrophys Harvard & Smithsonian, Atom & Mol Phys Div, MS50,60 Garden St, Cambridge, MA 02138 USA..
    Roueff, Evelyne
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Ryabchikova, Tatiana
    Russian Acad Sci, Inst Astron, Pyatnitskaya 48, Moscow 119017, Russia..
    Sahal-Brechot, Sylvie
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Scheier, Paul
    Univ Innsbruck, Inst Ion Phys & Appl Phys, Technikerstr 25-3, A-6020 Innsbruck, Austria..
    Schilke, Peter
    Univ Cologne, Phys Inst 1, Zulpicher Str 77, D-50937 Cologne, Germany..
    Schlemmer, Stephan
    Univ Cologne, Phys Inst 1, Zulpicher Str 77, D-50937 Cologne, Germany..
    Smith, Ken W.
    Queens Univ Belfast, Sch Math & Phys, Univ Rd, Belfast BT7 1NN, Antrim, North Ireland..
    Schmitt, Bernard
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Skobelev, Igor Yu.
    Natl Res Nucl Univ, Moscow Engn Phys Inst MEPhI, Moscow 115409, Russia.;Russian Acad Sci, Joint Inst High Temp, Moscow 141570, Russia..
    Sreckovic, Vladimir A.
    Univ Belgrade, Inst Phys Belgrade, POB 57, Belgrade 11001, Serbia..
    Stempels, H. C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Tashkun, Serguey A.
    Russian Acad Sci, Siberian Branch, VE Zuev Inst Atmospher Opt, Zuev Sq 1, Tomsk 634055, Russia..
    Tennyson, Jonathan
    UCL, Dept Phys & Astron, London WC1E 6BT, England..
    Tyuterev, Vladimir G.
    Tomsk State Univ, Phys Dept, Lab Quantum Mech & Radiat Transfer QUAMER, Tomsk 634050, Russia.;UFR Sci, CNRS, Grp Spectrometr Mol & Atmospher GSMA, UMR 7331, BP 1039-51687, Reims 2, France..
    Vastel, Charlotte
    Univ Toulouse UPS, Inst Rech Astrophys & Planetol, CNRS, CNES, 9 Av Colonel Roche, F-31028 Toulouse 4, France..
    Vujcic, Veljko
    Astron Observ, Volgina 7, Belgrade 11060, Serbia.;Univ Belgrade, Fac Org Sci, Jove Ilica 33, Belgrade 11000, Serbia..
    Wakelam, Valentine
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Walton, Nicholas A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Zeippen, Claude
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    Zwolf, Carlo Maria
    Univ Paris 06, Sorbonne Univ, UPMC, CNRS,LERMA,Observ Paris,PSL Res Univ, 5 Pl Janssen, F-92190 Meudon, France..
    A Decade with VAMDC: Results and Ambitions2020In: Atoms, E-ISSN 2218-2004, Vol. 8, no 4, article id 76Article in journal (Refereed)
    Abstract [en]

    This paper presents an overview of the current status of the Virtual Atomic and Molecular Data Centre (VAMDC) e-infrastructure, including the current status of the VAMDC-connected (or to be connected) databases, updates on the latest technological development within the infrastructure and a presentation of some application tools that make use of the VAMDC e-infrastructure. We analyse the past 10 years of VAMDC development and operation, and assess their impact both on the field of atomic and molecular (A&M) physics itself and on heterogeneous data management in international cooperation. The highly sophisticated VAMDC infrastructure and the related databases developed over this long term make them a perfect resource of sustainable data for future applications in many fields of research. However, we also discuss the current limitations that prevent VAMDC from becoming the main publishing platform and the main source of A&M data for user communities, and present possible solutions under investigation by the consortium. Several user application examples are presented, illustrating the benefits of VAMDC in current research applications, which often need the A&M data from more than one database. Finally, we present our vision for the future of VAMDC.

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  • 79.
    Alcusa-Saez, E. P.
    et al.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Diez, A.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Margulis, Walter
    KTH, School of Engineering Sciences (SCI), Applied Physics. Acreo AB, Dept Fiber Photon, Elect 236, S-16440 Kista, Sweden..
    Norin, Lars
    KTH, School of Engineering Sciences (SCI), Applied Physics. Acreo AB, Dept Fiber Photon, Elect 236, S-16440 Kista, Sweden..
    Andres, M. V.
    ICMUV, Dept Fis Aplicada & Electromagnetismo, Dr Moliner 50, Burjassot 46100, Spain..
    Acousto-optic interaction in polyimide coated optical fibers2017In: 2017 CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE & EUROPEAN QUANTUM ELECTRONICS CONFERENCE (CLEO/EUROPE-EQEC), IEEE , 2017Conference paper (Refereed)
  • 80. Alessi, D
    et al.
    Martz, Dale
    Colorado State Univ, Engn Res Ctr Extreme Ultraviolet Sci & Technol.
    Wang, Y
    Berrill, M
    Luther, B M
    Rocca, J J
    Gain-saturated 10.9 nm tabletop laser operating at 1 Hz repetition rate2010In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 35, no 3, p. 414-6Article in journal (Refereed)
    Abstract [en]

    We report the demonstration of a gain-saturated 10.9 nm tabletop soft x-ray laser operating at 1 Hz repetition rate. Lasing occurs by collisional electron impact excitation in the 4dS01-->4pP11 transition of nickel-like Te in a line-focus plasma heated by a chirped-pulse-amplification Ti:sapphire laser. With an average power of 1muW and pulse energy up to approximately 2microJ, this laser extends the ability to conduct tabletop laser experiments to a shorter wavelength.

  • 81. Alessi, D.
    et al.
    Wang, Y.
    Luther, B. M.
    Yin, L.
    Martz, D. H.
    epartment of Electrical and Computer Engineering, Colorado State University, Fort Collins, Colorado.
    Woolston, M. R.
    Liu, Y.
    Berrill, M.
    Rocca, J. J.
    Efficient Excitation of Gain-Saturated Sub-9-nm-Wavelength Tabletop Soft-X-Ray Lasers and Lasing Down to 7.36 nm2011In: Physical Review X, E-ISSN 2160-3308, Vol. 1, no 2Article in journal (Refereed)
    Abstract [en]

    We have demonstrated the efficient generation of sub-9-nm-wavelength picosecond laser pulses of microjoule energy at 1-Hz repetition rate with a tabletop laser. Gain-saturated lasing was obtained at λ=8.85  nm in nickel-like lanthanum ions excited by collisional electron-impact excitation in a precreated plasma column heated by a picosecond optical laser pulse of 4-J energy. Furthermore, isoelectronic scaling along the lanthanide series resulted in lasing at wavelengths as short as λ=7.36  nm. Simulations show that the collisionally broadened atomic transitions in these dense plasmas can support the amplification of subpicosecond soft-x-ray laser pulses.

  • 82.
    Ali, Hasan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Material Science. Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden.;Forschungszentrum Julich, Ernst Ruska Ctr Microscopy & Spect Electrons & Pe, D-52425 Julich, Germany..
    Sathyanath, Sharath Kumar Manjeshwar
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Material Science.
    Tai, Cheuk-Wai
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Rusz, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Uusimaki, Toni
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Hjörvarsson, Björgvin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Thersleff, Thomas
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Leifer, Klaus
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Material Science.
    Single scan STEM-EMCD in 3-beam orientation using a quadruple aperture2023In: Ultramicroscopy, ISSN 0304-3991, E-ISSN 1879-2723, Vol. 251, article id 113760Article in journal (Refereed)
    Abstract [en]

    The need to acquire multiple angle-resolved electron energy loss spectra (EELS) is one of the several critical challenges associated with electron magnetic circular dichroism (EMCD) experiments. If the experiments are performed by scanning a nanometer to atomic-sized electron probe on a specific region of a sample, the precision of the local magnetic information extracted from such data highly depends on the accuracy of the spatial registration between multiple scans. For an EMCD experiment in a 3-beam orientation, this means that the same specimen area must be scanned four times while keeping all the experimental conditions same. This is a non-trivial task as there is a high chance of morphological and chemical modification as well as non-systematic local orientation variations of the crystal between the different scans due to beam damage, contamination and spatial drift. In this work, we employ a custom-made quadruple aperture to acquire the four EELS spectra needed for the EMCD analysis in a single electron beam scan, thus removing the above-mentioned complexities. We demonstrate a quantitative EMCD result for a beam convergence angle corresponding to sub-nm probe size and compare the EMCD results for different detector geometries.

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  • 83.
    Ali, S.
    et al.
    Univ Stockholm, Dept Phys, S-10691 Stockholm, Sweden.
    Orban, I.
    Univ Stockholm, Dept Phys, S-10691 Stockholm, Sweden.
    Mahmood, S.
    Univ Stockholm, Dept Phys, S-10691 Stockholm, Sweden.
    Altun, Z.
    Marmara Univ, Dept Phys, TR-81040 Istanbul, Turkey.
    Glans, Peter
    Mid Sweden University, Faculty of Science, Technology and Media, Department of applied science and design.
    Schuch, R.
    Univ Stockholm, Dept Phys, S-10691 Stockholm, Sweden.
    ELECTRON-ION RECOMBINATION RATE COEFFICIENTS FOR C II FORMING C I2012In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 753, no 2, p. Art. no. 132-Article in journal (Refereed)
    Abstract [en]

    We have determined absolute dielectronic recombination rate coefficients for C II, using the CRYRING heavy-ions storage ring. The resonances due to 2s-2p (Delta n= 0) core excitations are detected in the center-of-mass energy range of 0-15 eV. The experimental results are compared with intermediate coupling AUTOSTRUCTURE calculations. Plasma rate coefficients are obtained from the DR spectrum by convoluting it with a Maxwell-Boltzmann energy distribution for temperatures in the range of 10(3)-10(6) K. The derived temperature-dependent plasma recombination rate coefficients are presented graphically and parameterized by using a fit formula for convenient use in plasma modeling codes. The experimental rate coefficients are also compared with the theoretical data available in literature. In the temperature range of 10(3)-2 x 10(4) K, our experimental results show that previous calculations severely underestimate the plasma rate coefficients and also our AUTOSTRUCTURE calculation does not reproduce the experimental plasma rate coefficients well. Above 2x10(4) K, the agreement between the experimental and theoretical rate coefficients is much better, and the deviations are smaller than the estimated uncertainties.

  • 84.
    Ali, Safdar
    Stockholm University, Faculty of Science, Department of Physics.
    Electron - Ion Recombination Data for Plasma Applications: Results from Electron Beam Ion Trap and Ion Storage Ring2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis contains results of electron-ion recombination processes in atomic ions relevant for plasma applications. The measurements were performed at the Stockholm Refrigerated Electron Beam Ion Trap (R-EBIT) and at the CRYRING heavy-ion storage ring. Dielectronic recombination (DR) cross sections, resonant strengths, rate coefficients and energy peak positions in H-like and He-like S are obtained for the first time from the EBIT measurements. Furthermore, the experimentally obtained DR resonant strengths are used to check the behaviour of a scaling formula for low Z, H-and He-like iso-electronic sequences and to update the fitting parameters. KLL DR peak positions for initially He- to B-like Ar ions are obtained experimentally from the EBIT measurements. Both the results from highly charged sulfur and argon are compared with the calculations performed with a distorted wave approximation.

    Absolute recombination rate coefficients of B-like C, B-like Ne and Be-like F ions are obtained for the first time with high energy resolution from storage ring measurements. The experimental results are compared with the intermediate coupling AUTOSTRUCTURE calculations. Plasma rate coefficients of each of these ions are obtained by convoluting the energy dependent recombination spectra with a Maxwell-Boltzmann energy distribution in the temperature range of 103-106 K. The resulting plasma rate coefficients are presented and compared with the calculated data available in literature.

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  • 85.
    Ali, Safdar
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Mahmood, Sultan
    Stockholm University, Faculty of Science, Department of Physics.
    Orban, Istvan
    Stockholm University, Faculty of Science, Department of Physics.
    Tashenov, Stanislav
    Stockholm University, Faculty of Science, Department of Physics.
    Li, Y. M.
    Wu, Z.
    Schuch, Reinhold
    Stockholm University, Faculty of Science, Department of Physics.
    Electron-ion recombination of H- and He-like sulfur2011In: Journal of Physics B: Atomic, Molecular and Optical Physics, ISSN 0953-4075, E-ISSN 1361-6455, Vol. 44, no 22, p. 225203-Article in journal (Refereed)
    Abstract [en]

    Electron-ion recombination of sulfur ions with electrons in the energy range of 1.6-3 keV was studied at the Stockholm Refrigerated Electron Beam Ion Trap. We obtained the KLn dielectronic recombination (DR) cross sections up to n = 5 for H-like and He-like sulfur ions by observing the x-rays from the trapped ions. A fully relativistic distorted wave approximation method was used for calculating the DR cross sections, while the resonance energies were obtained with a multiconfiguration Dirac-Fock approach using the GRASP II code. The calculations agree with the experimental results within the experimental error bars. Additionally, the obtained total DR resonance strengths were used to check the behaviour of a scaling formula for low-Z, He-like iso-electronic sequence (Watanabe et al 2001 J. Phys. B: At. Mol. Opt. Phys. 34 5095).

  • 86.
    Ali, Safdar
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Mahmood, Sultan
    Stockholm University, Faculty of Science, Department of Physics.
    Orban, Istvan
    Stockholm University, Faculty of Science, Department of Physics.
    Tashenov, Stanislav
    Stockholm University, Faculty of Science, Department of Physics.
    Li, Y. M.
    Wu, Z.
    Schuch, Reinhold
    Stockholm University, Faculty of Science, Department of Physics.
    Photo-recombination studies at R-EBIT with a Labview control and data = quisition system2011In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 6, p. C01016-Article in journal (Refereed)
    Abstract [en]

    Equipment at the Stockholm Refrigerated Electron Beam Ion Trap (R-EBIT) was developed for photo-recombination studies. A LabView-based event mode data acquisition and R-EBIT control system was implemented. The energies of KLL dielectronic recombination resonances in Li- to C-like argon ions were determined and compared with theoretical calculations performed using a distorted wave approximation. The theoretical and experimental peak positions for Li-, Be-, and C-like argon ions agree within the error bars. For B-like argon we observe an energy shift of 9 eV between the experimentally obtained peak position and the calculated result.

  • 87.
    Allum, Felix
    et al.
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Burt, Michael
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Amini, Kasra
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Boll, Rebecca
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Kockert, Hansjochen
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Olshin, Pavel K.
    St Petersburg State Univ, 7-9 Univ Skaya Nab, St Petersburg 199034, Russia.
    Bari, Sadia
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Bomme, Cedric
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Brausse, Felix
    Max Born Inst, Max Born Str 2A, D-12489 Berlin, Germany.
    de Miranda, Barbara Cunha
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Duesterer, Stefan
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Erk, Benjamin
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Geleoc, Marie
    Univ Paris Saclay, LIDYL, CEA, CNRS,CEA Saclay, F-91191 Gif Sur Yvette, France.
    Geneaux, Romain
    Univ Paris Saclay, LIDYL, CEA, CNRS,CEA Saclay, F-91191 Gif Sur Yvette, France.
    Gentleman, Alexander S.
    Univ Oxford, Phys & Theoret Chem Lab, Dept Chem, Oxford OX1 3QZ, England.
    Goldsztejn, Gildas
    Max Born Inst, Max Born Str 2A, D-12489 Berlin, Germany.
    Guillemin, Renaud
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Holland, David M. P.
    Daresbury Lab, Warrington WA4 4AD, Cheshire, England.
    Ismail, Iyas
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Johnsson, Per
    Lund Univ, Dept Phys, S-22100 Lund, Sweden.
    Journel, Loic
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Kuepper, Jochen
    Deutsch Elektronen Synchrotron DESY, Ctr Free Electron Laser Sci, Notkestr 85, D-22607 Hamburg, Germany;Univ Hamburg, Ctr Ultrafast Imaging, Luruper Chaussee 149, D-22761 Hamburg, Germany;Univ Hamburg, Dept Phys, Luruper Chaussee 149, D-22761 Hamburg, Germany;Univ Hamburg, Dept Chem, Martin Luther King Pl 6, D-20146 Hamburg, Germany.
    Lahl, Jan
    Lund Univ, Dept Phys, S-22100 Lund, Sweden.
    Lee, Jason W. L.
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Maclot, Sylvain
    Lund Univ, Dept Phys, S-22100 Lund, Sweden.
    Mackenzie, Stuart R.
    Univ Oxford, Phys & Theoret Chem Lab, Dept Chem, Oxford OX1 3QZ, England.
    Manschwetus, Bastian
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Mereshchenko, Andrey S.
    St Petersburg State Univ, 7-9 Univ Skaya Nab, St Petersburg 199034, Russia.
    Mason, Robert
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Palaudoux, Jerome
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Piancastelli, Maria Novella
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics. Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Penent, Francis
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Rompotis, Dimitrios
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany;European XFEL, Holzkoppel 4, D-22869 Schenefeld, Germany.
    Rouzee, Arnaud
    Max Born Inst, Max Born Str 2A, D-12489 Berlin, Germany.
    Ruchon, Thierry
    Univ Paris Saclay, LIDYL, CEA, CNRS,CEA Saclay, F-91191 Gif Sur Yvette, France.
    Rudenko, Artem
    Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA.
    Savelyev, Evgeny
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Simon, Marc
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Schirmel, Nora
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Stapelfeldt, Henrik
    Aarhus Univ, Dept Chem, Langelandsgade 140, DK-8000 Aarhus C, Denmark.
    Techert, Simone
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany;Max Planck Inst Biophys Chem, D-37077 Gottingen, Germany;Univ Gottingen, Inst Xray Phys, D-37077 Gottingen, Germany.
    Travnikova, Oksana
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Trippel, Sebastian
    Deutsch Elektronen Synchrotron DESY, Ctr Free Electron Laser Sci, Notkestr 85, D-22607 Hamburg, Germany;Univ Hamburg, Ctr Ultrafast Imaging, Luruper Chaussee 149, D-22761 Hamburg, Germany.
    Underwood, Jonathan G.
    UCL, Dept Phys & Astron, London WC1E 6BT, England.
    Vallance, Claire
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Wiese, Joss
    Deutsch Elektronen Synchrotron DESY, Ctr Free Electron Laser Sci, Notkestr 85, D-22607 Hamburg, Germany;Univ Hamburg, Dept Chem, Martin Luther King Pl 6, D-20146 Hamburg, Germany.
    Ziaee, Farzaneh
    Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA.
    Brouard, Mark
    Univ Oxford, Chem Res Lab, Dept Chem, Oxford OX1 3TA, England.
    Marchenko, Tatiana
    Sorbonne Univ, LCPMR, CNRS, F-75005 Paris, France.
    Rolles, Daniel
    Kansas State Univ, Dept Phys, JR Macdonald Lab, Manhattan, KS 66506 USA.
    Coulomb explosion imaging of CH3I and CH2CII photodissociation dynamics2018In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 149, no 20, article id 204313Article in journal (Refereed)
    Abstract [en]

    The photodissociation dynamics of CH3I and CH2CII at 272 nm were investigated by time-resolved Coulomb explosion imaging, with an intense non-resonant 815nmprobe pulse. Fragment ion momenta over a widem/z range were recorded simultaneously by coupling a velocity map imaging spectrometer with a pixel imaging mass spectrometry camera. For both molecules, delay-dependent pump-probe features were assigned to ultraviolet-induced carbon-iodine bond cleavage followed by Coulomb explosion. Multi-mass imaging also allowed the sequential cleavage of both carbon-halogen bonds in CH2ClI to be investigated. Furthermore, delay-dependent relative fragment momenta of a pair of ions were directly determined using recoil-frame covariance analysis. These results are complementary to conventional velocity map imaging experiments and demonstrate the application of time-resolved Coulomb explosion imaging to photoinduced real-time molecular motion.

  • 88.
    Almlöf, Jonas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum Electronics and Quantum Optics, QEO.
    Quantum error correction2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Quantum error correction is the art of protecting quantum states from the detrimental influence from the environment. To master this art, one must understand how the system interacts with the environment and gives rise to a full set of quantum phenomena, many of which have no correspondence in classical information theory. Such phenomena include decoherence, an effect that in general destroys superpositions of pure states as a consequence of entanglement with the environment. But decoherence can also be understood as “information leakage”, i.e., when knowledge of an encoded code block is transferred to the environment. In this event, the block’s information or entanglement content is typically lost.

    In a typical scenario, however, not all types of destructive events are likely to occur, but only those allowed by the information carrier, the type of interaction with the environment, and how the environment “picks up” information of the error events. These characteristics can be incorporated into a code, i.e., a channel-adapted quantum error-correcting code.

    Often, it is assumed that the environment’s ability to distinguish between error events is small, and I will denote such environments “memory-less”. But this assumption is not always valid, since the ability to distinguish error events is related to the temperature of the environment, and in the particular case of information coded onto photons, kBTR «ℏω typically holds, and one must then assume that the environment has a “memory”. In the thesis I describe a short quantum error-correction code adapted for photons interacting with a “cold” reservoir, i.e., a reservoir which continuously probes what error occurred in the coded state.

    I also study other types of environments, and show how to distill meaningful figures of merit from codes adapted for these channels, as it turns out that resource-based figures reflecting both information and entanglement can be calculated exactly for a well-studied class of channels: the Pauli channels. Starting from these resource-based figures, I establish the notion of efficiency and quality and show that there will be a trade-off between efficiency and quality for short codes. Finally I show how to incorporate, into these calculations, the choices one has to make when handling quantum states that have been detected as incorrect, but where no prospect of correcting them exists, i.e., so-called detection errors.

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    Thesis
  • 89.
    Almlöf, Jonas
    et al.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Quantum Electronics and Quantum Optics, QEO.
    Björk, Gunnar G. E.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Quantum Electronics and Quantum Optics, QEO.
    A short and efficient error correcting code for polarization coded photonic qubits in a dissipative channel2011In: Optics Communications, ISSN 0030-4018, E-ISSN 1873-0310, Vol. 284, no 1, p. 550-554Article in journal (Refereed)
    Abstract [en]

    We propose a short and efficient non-degenerate quantum error correcting code that is adapted for qubits encoded on two orthogonal, single-photon states (e.g., horizontally and vertically polarized) subject to a dissipative channel. The proposed code draws its strength from the fact that it is adapted to the physical characteristics of the information-carrying basis states under the action of the channel. The code combines different energy manifolds and consists of only 3 spatio-temporal modes and on average 2 photons per code word.

  • 90.
    Almlöf, Jonas
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum Electronics and Quantum Optics, QEO.
    Björk, Gunnar G. E.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Quantum Electronics and Quantum Optics, QEO.
    Fidelity as a figure of merit in quantum error correction2013In: Quantum information & computation, ISSN 1533-7146, Vol. 13, no 1-2, p. 0009-0020Article in journal (Refereed)
    Abstract [en]

    We discuss the fidelity as a figure of merit in quantum error correction schemes. We show that when identifiable but uncorrectable errors occur as a result of the action of the channel, a common strategy that improves the fidelity actually decreases the transmitted mutual information. The conclusion is that while the fidelity is simple to calculate and therefore often used, it is perhaps not always a recommendable figure of merit for quantum error correction. The reason is that while it roughly speaking encourages optimisation of the "mean probability of success", it gives no incentive for a protocol to indicate exactly where the errors lurk. For small error probabilities, the latter information is more important for the integrity of the information than optimising the mean probability of success.

  • 91.
    Al-Mulla, S Y Yousif
    University of Borås, School of Engineering.
    Modification of The Atomic Scattering Factor in Electric Field2014Conference paper (Refereed)
    Abstract [en]

    Quantum mechanical calculations of a modification of the X-ray scattering form factor of an atom/ion in an electric field using a three parameter wave function have been performed. These calculations are compared with the previous two parameter wave function calculations.

  • 92.
    Al-Mulla, S.Y.Yousif
    et al.
    University of Borås, School of Engineering.
    Jönsson, Lennart
    University of Borås, School of Engineering.
    Elastic Scattering of electrons from Lithium and Potassium2012Conference paper (Other academic)
  • 93.
    Almén, Anton
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Physics (from 2013).
    Photophysics of the polymer acceptor PF5-Y5 in organic photovoltaics: A first principles theory based study2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Non-fullerene Acceptors (NFAs) have gathered a great deal of interest for use inorganic photovoltaics (OPVs) due to recent breakthroughs in their power conversion efficiency and other advantages they offer over their Fullerene-based counterparts.

    In this work, a new promising non-fullerene polymer acceptor, PF5-Y5, have been studied using density functional theory and time-dependent density functional theory; and the effects that oligomer length, geometry relaxation and exchange-correlation interaction has on the exciton binding energies (the difference between optical and fundamental energy gaps) have been investigated.

    Both the fundamental and optical gaps are significantly affected by the choice of functional (i.e., the description of the exchange-correlation interaction). However, it does not appear to significantly impact obtained exciton binding energies as the effects of the fundamental and optical gaps cancel each other out.

    Both the fundamental and optical energy gap are shown to slightly reduce as a function of the oligomer length (~0.1 - 0.3 𝑒𝑉 reduction for each repeated monomer). As both gaps are reduced by a similar amount per repeated monomer, they counteract each other and the total effect that oligomer length has on the exciton binding energy is very low.

    Geometry relaxation and thermal effects showed the largest impact on the fundamental gap and exciton binding energy, with their combined effect resulting in a ~0.5 𝑒𝑉 reduction in binding energy. 

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  • 94. Alonso, M. A.
    et al.
    Setala, T.
    Friberg, Ari T.
    KTH, School of Information and Communication Technology (ICT), Optics and Photonics, Optics.
    Optimal pulses for arbitrary dispersive media2011In: Journal of the European Optical Society-Rapid Publications, E-ISSN 1990-2573, Vol. 6, p. 11035-Article in journal (Refereed)
    Abstract [en]

    A variational procedure is given for finding the pulses for which the initial temporal rms width and the rate of increase of this width are jointly minimized for propagation in non-absorbing media with arbitrary dispersive properties. We show that, while in linearly dispersive media the optimal pulses are Gaussian, in other situations such as a hollow metallic waveguide or for purely cubic dispersion departures from Gaussian behavior become evident. An interpretation of the results in terms of suitable phase-space representations is also given.

  • 95. Alonso-Mori, R.
    et al.
    Asa, K.
    Bergmann, U.
    Brewster, A. S.
    Chatterjee, R.
    Cooper, J. K.
    Frei, H. M.
    Fuller, F. D.
    Goggins, E.
    Gul, S.
    Fukuzawa, H.
    Iablonskyi, D.
    Ibrahim, M.
    Katayama, T.
    Kroll, T.
    Kumagai, Y.
    McClure, B. A.
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Motomura, K.
    Nagaya, K.
    Nishiyama, T.
    Saracini, C.
    Sato, Y.
    Sauter, N. K.
    Sokaras, D.
    Takanashi, T.
    Togashi, T.
    Ueda, K.
    Weare, W. W.
    Weng, T-C
    Yabashi, M.
    Yachandra, V. K.
    Young, I. D.
    Zouni, A.
    Kern, J. F.
    Yano, J.
    Towards characterization of photo-excited electron transfer and catalysis in natural and artificial systems using XFELs2016In: Faraday discussions, ISSN 1359-6640, E-ISSN 1364-5498, Vol. 194, p. 621-638Article in journal (Refereed)
    Abstract [en]

    The ultra-bright femtosecond X-ray pulses provided by X-ray Free Electron Lasers (XFELs) open capabilities for studying the structure and dynamics of a wide variety of biological and inorganic systems beyond what is possible at synchrotron sources. Although the structure and chemistry at the catalytic sites have been studied intensively in both biological and inorganic systems, a full understanding of the atomic-scale chemistry requires new approaches beyond the steady state X-ray crystallography and X-ray spectroscopy at cryogenic temperatures. Following the dynamic changes in the geometric and electronic structure at ambient conditions, while overcoming X-ray damage to the redox active catalytic center, is key for deriving reaction mechanisms. Such studies become possible by using the intense and ultra-short femtosecond X-ray pulses from an XFEL, where sample is probed before it is damaged. We have developed methodology for simultaneously collecting X-ray diffraction data and X-ray emission spectra, using an energy dispersive spectrometer, at ambient conditions, and used this approach to study the room temperature structure and intermediate states of the photosynthetic water oxidizing metallo-protein, photosystem II. Moreover, we have also used this setup to simultaneously collect the X-ray emission spectra from multiple metals to follow the ultrafast dynamics of light-induced charge transfer between multiple metal sites. A Mn-Ti containing system was studied at an XFEL to demonstrate the efficacy and potential of this method.

  • 96.
    AlSalhi, M S.
    et al.
    King Saud University, Saudi Arabia .
    Atif, M
    King Saud University, Saudi Arabia; National Institute of Laser and Optronics, Nilore, Islamabad, Pakistan.
    Ansari, A A.
    King Saud University, Saudi Arabia .
    Khun, Kimleang
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Hussain Ibupoto, Zafar
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology. King Saud University, Riyadh, Saudi Arabia.
    Growth and characterization of ZnO nanowires for optical applications2013In: Laser physics, ISSN 1054-660X, E-ISSN 1555-6611, Vol. 23, no 6, article id 065602Article in journal (Refereed)
    Abstract [en]

    In the present work, cerium oxide CeO2 nanoparticles were synthesized by the sol-gel method and used for the growth of ZnO nanorods. The synthesized nanoparticles were studied by x-ray diffraction (XRD) and Raman spectroscopic techniques. Furthermore, these nanoparticles were used as the seed layer for the growth of ZnO nanorods by following the hydrothermal growth method. The structural study of ZnO nanorods was carried out by means of field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and XRD techniques. This study demonstrated that the grown ZnO nanorods are well aligned, uniform, of good crystal quality and have diameters of less than 200 nm. Energy dispersive x-ray (EDX) analysis revealed that the ZnO nanorods are composed only of zinc, cerium as the seed atom, and oxygen atoms, with no other impurities in the grown nanorods. Moreover, a photoluminescence (PL) approach was applied for the optical characterization, and it was observed that the near-band-edge (NBE) emission was the same as that of the zinc acetate seed layer, however the green and orange/red emission peaks were slightly raised due to possibly higher levels of defects in the cerium oxide seeded ZnO nanorods. This study provides an alternative approach for the controlled synthesis of ZnO nanorods using cerium oxide nanoparticles as the seed nucleation layer, improving both the morphology of the nanorods and the performance of devices based upon them.

  • 97. Alsmeyer, H
    et al.
    Albrecht, G
    Meyer, L
    Hafner, W
    Journeau, C
    Fischer, M
    Hellman, S
    Eddi, M
    Allelein, H J
    Burger, M
    Sehgal, Balraj
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Power Safety.
    Koch, M K
    Alkan, Z
    Petrov, J B
    Gaune-Escard, M
    Altstadt, E
    Bandini, G
    Ex-vessel core melt stabilization research (ECOSTAR)2005In: Nuclear Engineering and Design, ISSN 0029-5493, E-ISSN 1872-759X, Vol. 235, no 2-4, p. 271-284Article in journal (Refereed)
    Abstract [en]

    The project on ex-vessel core melt stabilization research (ECOSTAR) started in January 2000 to be concluded by end of 2003. The project is performed by 14 partner institutions from five European countries and involves a large number of experiments with low- and high-temperature simulant melts and real corium at different scales. Model development and scaling analysis allows application of the research results to existing and to future LWRs in the area of reactor design and accident mitigation. The project is oriented toward the analysis and mitigation of severe accident sequences that could occur in the ex-vessel phase of a postulated core melt accident. The issues are: (1) the release of melt form the pressure vessel, (2) the transfer and spreading of the melt on the basement, (3) the analysis of the physical-chemical processes that are important for corium behavior especially during concrete erosion with onset of solidification, and (4) stabilization of the melt by cooling through direct water contact. The results achieved so far resolve a number of important issues: the amount of melt that could be transferred at RPV failure from the RPV into the containment can be substantially reduced by lowering the residual pressure in the primary circuit. It is found that melt dispersion also strongly depends on the location of the RPV failure, and that lateral failure results in substantially less melt dispersion. During melt release, the impinging melt jet could erode parts of the upper basement surface. Jet experiments and a derived heat transfer relation allow estimation of its contribution to concrete erosion. Spreading of the corium melt on the available basement surface is an important process, which defines the initial conditions for concrete attack or for the efficiency of cooling in case of water contact, respectively. Validation of the spreading codes based on a large-scale benchmark experiment is underway and will allow determination of the initial conditions, for which a corium melt can be assumed to spread homogeneously over the available surface. Experiments with UO(2)-based corium melts highlight the role of phase segregation during onset of melt solidification and during concrete erosion. To cool the spread corium melt, the efficacy of top flooding and bottom flooding is investigated in small-scale and in large-scale experiments, supported by model developments. Project assessment is continuing to apply the results to present and future reactors.

  • 98.
    Altmann, Robert
    et al.
    Univ Augsburg, Dept Math, Univ Str 14, D-86159 Augsburg, Germany..
    Henning, Patrick
    KTH, School of Engineering Sciences (SCI), Mathematics (Dept.), Numerical Analysis, NA. Ruhr Univ Bochum, Fac Math, D-44801 Bochum, Germany..
    Peterseim, Daniel
    Univ Augsburg, Dept Math, Univ Str 14, D-86159 Augsburg, Germany..
    Localization And Delocalization Of Ground States Of Bose-Einstein Condensates Under Disorder2022In: SIAM Journal on Applied Mathematics, ISSN 0036-1399, E-ISSN 1095-712X, Vol. 82, no 1, p. 330-358Article in journal (Refereed)
    Abstract [en]

    This paper studies the localization behavior of Bose-Einstein condensates in disorder potentials, modeled by a Gross-Pitaevskii eigenvalue problem on a bounded interval. In the regime of weak particle interaction, we are able to quantify exponential localization of the ground state, depending on statistical parameters and the strength of the potential. Numerical studies further show delocalization if we leave the identified parameter range, which is in agreement with experimental data. These mathematical and numerical findings allow the prediction of physically relevant regimes where localization of ground states may be observed experimentally.

  • 99.
    Alvarez Ruiz, Jesus
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Atomic and Molecular Physics.
    Melero-Garcia, Emilio
    KTH, School of Engineering Sciences (SCI), Physics, Atomic and Molecular Physics.
    Kivimäki, Antti
    Coreno, M.
    Erman, Peter
    KTH, School of Engineering Sciences (SCI), Physics.
    Rachlew, Elisabeth
    KTH, School of Engineering Sciences (SCI), Physics.
    Richter, R.
    Synchrotron radiation induced fluorescence spectroscopy of SF62005In: Journal of Physics B: Atomic, Molecular and Optical Physics, ISSN 0953-4075, E-ISSN 1361-6455, Vol. 38, p. 387-Article in journal (Refereed)
    Abstract [en]

    The fluorescence of gaseous SF6 was investigated after excitation with 25-80eV synchrotron radiation photons. The total UV-Vis-near IR fluorescence yield was recorded and interpreted in terms of inner valence excitations/ionizations and double excitations in SF6. Dispersed fluorescence measurements in the 400-1000 nm spectral range reveal excited S, S+, F and F+ fragments as solely responsible for the emission. The fluorescence intensity of some of the observed atomic transitions was monitored as a function of the excitation energy. Single, double and triple excitations as well as direct ionizations and shake-ups are proposed as the triggering processes responsible for the creation of the emitting fragments.

  • 100.
    Alves, Gabriel O.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy. Instituto de Fiısica da Universidade de Sao Paulo, Brazil.
    Sjöqvist, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Quantum Matter Theory.
    Time-optimal holonomic quantum computation2022In: Physical review A : covering atomic, molecular, and optical physics and quantum information, ISSN 2469-9926, Vol. 106, article id 032406Article in journal (Refereed)
    Abstract [en]

    A three-level system can be used in a Λ-type configuration in order to construct a universal set of quantum gates through the use of non-Abelian non-adiabatic geometrical phases. Such construction allows for high- speed operation times which diminish the effects of decoherence. This might be, however, accompanied by a breakdown of the validity of the rotating wave approximation (RWA) due to the comparable time scale between counter rotating terms and pulse length, which greatly affects the dynamics. Here, we investigate the trade- off between dissipative effects and the RWA validity, obtaining the optimal regime for the operation of the holonomic quantum gates.

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