Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Fluorescent material has been imaged using Pulsed Digital Holographic Interferometry. The fluorescent molecule Coumarin 153 dissolved in ethanol was excited to a higher energetic state(pumping) with a 355nm laser beam(Pump beam), giving rise to a broad spontaneous emission spectrum. A second laser beam of wavelength 532nm(Probe beam) was propagated through the excited volume(probing) and recorded after passage using both conventional pulse energy monitoring and Digital Holography. Due to stimulated emission, an increase in probe beam energy could be recorded, while spectroscopic measurements showed a decrease in intensity over the entire spontaneous emission spectrum. The experiment was repeated for different molecular concentrations and probe beam energies. A theoretical mode connecting the gain of the probe beam to concentration and probe beam energy has been derived and compared with experimental results. The model predicts an increasing gain for higher concentrations but also a decrease in gain for higher probe beam energies. Results show that for low concentrations, up to 0.053g/L, the gain follows the general trend of the model where a maximum gain of 13% has been observed. For the concentration 0.032g/L a maximum gain of 39% has been observed. The phase response has also been investigated. No change in phase directly resulting from the stimulated emission effect was observed, however, results show that thermal effects may be studied from the holographic recordings.
Place, publisher, year, edition, pages
2013. , 38 p.
digital holografi, fluorescens, optisk metrologi
IdentifiersURN: urn:nbn:se:ltu:diva-56779Local ID: d860ca74-88d1-45fd-8414-103a58bd0188OAI: oai:DiVA.org:ltu-56779DiVA: diva2:1030166
Subject / course
Student thesis, at least 30 credits
Engineering Physics and Electrical Engineering, master's level
Validerat; 20130501 (global_studentproject_submitter)2016-10-042016-10-04Bibliographically approved