Absorption in GaAs/AlGaAs quantum wells with barriers and resonant interband tunneling in InAs/GaSb/AlSb polytype structures

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7044966

Kiledjian, M S

A modified GaAs quantum well structure with high responsivity has been devised. The modification includes putting small barriers on the sides of the quantum well to increase absorption from the bound to an extended state; thus, optimizing device performance by increasing the amplitude of the extended state wavefunction in the well region. The width and the height of the barriers can be modified to control the spectrum of absorption. The analysis was done using a two-band tight-binding method to calculate the wavefunctions. The results indicate that in general the bigger and the wider the barriers, the narrower and the larger the absorption is, and the stronger the resonance becomes. Next, the tunneling of holes in a double-barrier GaAs/GaAlAs heterostructure and interband tunneling in several InAs/AlSb heterostructure were calculated. A ten-band tight binding model was used in order to incorporate mixing between the bands. The model was solved using a new method which allows many-layer structures to be handled without numerical instabilities. It is found that the mixing between the bands has a significant effect on the current-voltage characteristics, especially with the inclusion of the dependence of the transmission on the parallel component of the incident wavevector (k[sub [parallel]]). In addition, the large peak-to-valley ratios and the high peak current densities found for the InAs/AlSb/GaSb heterostructure will be useful for practical applications in high-speed digital and analog applications.

• Research Organization: California Univ., Los Angeles, CA (United States)
• OSTI ID: 7044966
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360606* -- Other Materials-- Physical Properties-- (1992-)
42 ENGINEERING
426000 -- Engineering-- Components
Electron Devices & Circuits-- (1990-)
ABSORPTION
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
ANTIMONIDES
ANTIMONY COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
BAND THEORY
GALLIUM ANTIMONIDES
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HETEROJUNCTIONS
HOLE MOBILITY
INDIUM ARSENIDES
INDIUM COMPOUNDS
JUNCTIONS
MOBILITY
PNICTIDES
POTENTIALS
SEMICONDUCTOR JUNCTIONS
SORPTION
TUNNEL EFFECT