Change search
ReferencesLink to record
Permanent link

Direct link
Dissipative Quantum Dynamics and Decoherence
Umeå University, Faculty of Science and Technology, Department of Physics.
2011 (English)Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Abstract This thesis has two parts, in the first, the Caldeira-Leggett model is introduced; its derivation and general consequences are explored following a paper by Caldeira and Leggett[1]. An operator-formalism shortcut through some of the more mathematically cumbersome parts of the derivation of the model is also developed. The correlation of the force resulting from reservoir-interaction is examined in the high- and low-temperature limits, and the Langevin equation is shown to emerge in the classical limit.Abstract The second part introduces decoherence through a thought experiment that demonstrates the destructive effect of random phase shifts on interference terms, and then follows another paper by Caldeira and Leggett[2] in applying their model further to study the phenomenon of dissipative decoherence. The time-evolution of the interference terms in a superposition of Gaussian wave packets in a harmonic oscillator potential is studied when interacting with a heat bath, and they are shown to vanish at a rate much faster than the relaxation of the system.

Place, publisher, year, edition, pages
2011. , 85 p.
Keyword [en]
decoherence, quantum mechanics, dissipation, caldeira-leggett
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:umu:diva-44341OAI: oai:DiVA.org:umu-44341DiVA: diva2:420243
Uppsok
Technology
Supervisors
Examiners
Available from: 2011-06-13 Created: 2011-05-31 Last updated: 2011-06-13Bibliographically approved

Open Access in DiVA

fulltext(615 kB)479 downloads
File information
File name FULLTEXT01.pdfFile size 615 kBChecksum SHA-512
0e9ee4d06bbb6ca3a6ae200f94f578505cb61fcc000e630fb232361b63fa5e41dd4abd4949e6199f25429432f4db41a7d40ecebf4adf7d2bd36d6a5e9a257469
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Löfgren, Viktor
By organisation
Department of Physics
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 479 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 135 hits
ReferencesLink to record
Permanent link

Direct link