Atomistic tight-binding study of electronic structure and interband optical transitions in GaBi{sub x}As{sub 1−x}/GaAs quantum wells

Journal Article · Mon Feb 17 04:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4865827· OSTI ID:22283133

Usman, Muhammad ^[1]; O'Reilly, Eoin P. ^[1]

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1. Tyndall National Institute, Lee Maltings, Dyke Parade, Cork (Ireland)

Large-supercell tight-binding calculations are presented for GaBi{sub x}As{sub 1−x}/GaAs single quantum wells (QWs) with Bi fractions x of 3.125% and 12.5%. Our results highlight significant distortion of the valence band states due to the alloy disorder. A large full-width-half-maximum (FWHM) is estimated in the ground state interband transition energy (≈33 meV) at 3.125% Bi, consistent with recent photovoltage measurements for similar Bi compositions. Additionally, the alloy disorder effects are predicted to become more pronounced as the QW width is increased. However, they are less strong at the higher Bi composition (12.5%) required for the design of temperature-stable lasers, with a calculated FWHM of ≈23.5 meV at x = 12.5%.

• OSTI ID: 22283133
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 7 Vol. 104; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
ABSORPTION SPECTROSCOPY
BISMUTH COMPOUNDS
CONCENTRATION RATIO
ELECTRONIC STRUCTURE
ENERGY-LEVEL TRANSITIONS
GALLIUM ARSENIDES
GROUND STATES
HETEROJUNCTIONS
LASER RADIATION
QUANTUM WELLS
VALENCE
X-RAY SPECTROSCOPY