High pressure optical studies of semiconductors and heterostructures. Final report

Technical Report · Wed Feb 01 04:00:00 EST 1995

DOI:https://doi.org/10.2172/10117108· OSTI ID:10117108

Chandrasekhar, H R

The authors have studied the effects of hydrostatic pressure on the confined transitions in quantum well heterostructures, using lattice matched GaAs/Al{sub x}GaAs{sub 1{minus}x}As, strained layer narrow band gap GaSb/AlSb and In{sub x}Ga{sub 1{minus}x}As/GaAs, and strained layer wide gap Zn{sub 1{minus}x}Cd{sub x}Se/ZnSe as examples. Precise values of the energies, pressure coefficients and band alignments are determined. In strained epilayers the interfacial strains, deformation potential constants and compressibilities are deduced. Strain compensation, structural stability and phase transitions are probed. The authors have observed a novel type of Fano resonance of excitons in GaAs associated with the {Gamma} conduction band as they hybridize with the X and L continua via electron-phonon coupling. This effect is used to extract the intervalley electron-phonon deformation potential D{sub {Gamma}X} to be 10.7 {+-} 0.7 eV/{angstrom}. They have observed a new electron trap state in Al{sub 0.3}Ga{sub 0.7}As doped with silicon at pressure of 60 kbar. They postulate that this new trap state has a large lattice relaxation with the trap energy well above the X CB. These trap states may be present in all Al{sub x}Ga{sub x}As materials and may be dominant at large x values (0.7 < x < 1).

• Research Organization: Missouri Univ., Columbia, MO (United States). Dept. of Physics and Astronomy
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-89ER45402
• OSTI ID: 10117108
• Report Number(s): DOE/ER/45402--T1; ON: DE95007119; BR: KC0202020
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360600
ALUMINIUM ARSENIDES
ALUMINIUM COMPOUNDS
CADMIUM SELENIDES
ELECTRON-PHONON COUPLING
ELECTRONIC STRUCTURE
ENERGY GAP
FANO FACTOR
GALLIUM ANTIMONIDES
GALLIUM ARSENIDES
HETEROJUNCTIONS
INDIUM ARSENIDES
LASER MATERIALS
LATTICE PARAMETERS
MAGNETIC PROPERTIES
OTHER MATERIALS
PROGRESS REPORT
RESEARCH PROGRAMS
SEMICONDUCTOR MATERIALS
ZINC SELENIDES