Atomistic tight-binding study of electronic structure and interband optical transitions in GaBixAs1-x/GaAs quantum wells

作者：Usman Muhammad^*; O' Reilly Eoin P

来源：Applied Physics Letters, 2014, 104(7): 071103.

DOI：10.1063/1.4865827

Large-supercell tight-binding calculations are presented for GaBixAs1-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 (approximate to 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 approximate to 23.5 meV at x = 12.5%.

• 出版日期2014-2-17