Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
- Publication
- Publication Type
Articles 1 - 3 of 3
Full-Text Articles in Physics
Intersubband Lasing Lifetimes Of Sige/Si And Gaas/Algaas Multiple Quantum Well Structures, Greg Sun, L. Friedman, Richard A. Soref
Intersubband Lasing Lifetimes Of Sige/Si And Gaas/Algaas Multiple Quantum Well Structures, Greg Sun, L. Friedman, Richard A. Soref
Physics Faculty Publications
The feasibility of population inversion is studied for the SiGe/Si system and compared with that of GaAs/AlGaAs. Because of the absence of strong polar optical phonon scattering in SiGe/Si, the lifetime difference of the upper and lower lasing levels, to which the population inversion and laser gain are proportional, is consistently an order of magnitude larger than that of GaAs/AlGaAs; nor does it show the sudden drop to zero or negative values when the lasing energy exceeds the optical phonon energy. Both systems studied are superlattices, each period of which consists of three coupled quantum wells and barriers.
Visible Luminescence From Single Crystal‐Silicon Quantum Wells, Peter N. Saeta, A. C. Gallagher
Visible Luminescence From Single Crystal‐Silicon Quantum Wells, Peter N. Saeta, A. C. Gallagher
All HMC Faculty Publications and Research
Single crystal‐silicon quantum wells with SiO2 barriers have been grown from SIMOX silicon‐on‐insulator substrates. Photoluminescence in the red and near‐infrared is observed for average well width <8 >nm, with peak signal for 2‐nm average width. The luminescence spectrum is independent of well width for SiO2 barriers, but shifts 0.3 eV to higher energy upon removal of the upper oxide layer with HF. Both results suggest the importance of radiation from surface states.
Compensation And Characterization Of Gallium Arsenide, Randy A. Roush
Compensation And Characterization Of Gallium Arsenide, Randy A. Roush
Electrical & Computer Engineering Theses & Dissertations
The properties of transition metals in gallium arsenide have been previously investigated extensively with respect to activation energies, but little effort has been made to correlate processing parameters with electronic characteristics. Diffusion of copper in gallium arsenide is of technological importance due to the development of GaAs:Cu bistable photoconductive devices. Several techniques are demonstrated in this work to develop and characterize compensated gallium arsenide wafers. The material is created by the thermal diffusion of copper into silicon-doped GaAs. Transition metals generally form deep and shallow acceptors in GaAs, and therefore compensation is possible by material processing such that the shallow …