2026-09-21T15:39:00Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/81147 2023-07-11 col_2142_5131 col_2142_8888 com_2142_5130 com_2142_8887 com_2142_234

Chuang, Shun-Lien Petschke, Adam Christopher 2015-09-25T20:09:45Z 2015-09-25T20:09:45Z 10000-01-01 2009 2009 83 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009. We also perform an experimental study of the role of the substrate on the optical and electrical properties. We find that the effect of the substrate thickness on the laser performance is dependent on other waveguide parameters. In particular, if the plasma layer is thick enough, the role of the substrate should be minimal. We use two-dimensional finite element modeling (FEM) to determine the threshold material gain coefficient and compare it to the experimental results of the threshold current density. We find that the threshold current density is roughly constant until the substrate thickness becomes smaller than 150 microm. Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only (MiAaPQ)AAI3392434 http://hdl.handle.net/2142/81147 eng Engineering, Electronics and Electrical Design, Fabrication, and Characterization of Terahertz Quantum Cascade Lasers text Electrical and Computer Engineering Electrical and Computer Engineering University of Illinois at Urbana-Champaign Dissertation Ph.D.