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Yoon, Howard Wuk 2011-05-07T13:23:15Z 2011-05-07T13:23:15Z 10000-01-01 1994 This thesis describes the use of optical absorption and photoluminescence spectroscopy in understanding the spatial transport and energy relaxation of excitons in quantum well systems. I discuss the mechanism of carrier-induced changes in the absorption spectrum of a 210A GaAs multiple quantum well, and show that at moderate densities, the enhanced transmission at the heavy-hole exciton energy is due to collision broadening. I also discuss the time dependent and excitation-energy dependent energy shifts of the heavy-hole exciton. I use the changes induced in the absorption spectra due to the presence of carriers as a probe for measuring the spatial transport, and I describe the transport using an ionized-impurity scattering model. I also measure the carrier temperatures from the high energy slopes of the time-resolved photoluminescence spectra, and describe the roles of the carrier temperatures and carrier expansion on the time dynamics of the exciton luminescence intensity. In the last chapter, I study the transport properties of excitons in an asymmetric-coupled quantum well system, and explain the experimental results with a model based on interface-roughness scattering. Made available in DSpace on 2011-05-07T13:23:15Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9503361.pdf: 5988113 bytes, checksum: 8ca1f2407fc3f5224a4cb6e0957e8765 (MD5) Previous issue date: 1994 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:54:06Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:25:06-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9503361 (UMI)AAI9503361 http://hdl.handle.net/2142/21921 eng Copyright 1994 Yoon, Howard Wuk Physics, Condensed Matter Physics, Optics Exciton transport and thermodynamics in gallium arsenide quantum wells text Physics Physics University of Illinois at Urbana-Champaign Dissertation Ph.D.