Abstract
The (12 x 12) and (14 x 14) valence band anticrossing (V-BAC) models were applied to calculate the electronic band structure of GaAs1-xBix dilute alloys along Delta-, Lambda- and Sigma-directions at room temperature. A comparative study based on these models was performed in terms of energy levels, optical transitions, spin-orbit splitting and effective mass. We found a significant reduction of the band-gap energy E-g by roughly 81 meV/%Bi accompanied by an increase in the spin-orbit splitting Delta(so+) by about 56 meV/%Bi. Furthermore, Delta(so+) does come into resonance with E-g at similar to 12%Bi for resonance energy equal to 0.73 eV. An excellent agreement has occurred between the (14 x 14) V-BAC model predictions and experimental results reported in the literature. In addition, we have investigated the Bi composition and k-directions dependence of the effective mass at Gamma point. A slight increase of the holes effective mass with x can affect the holes transport properties of GaAsBi. The intrinsic carrier density increases with both x and the temperature T, but it remains below 10(10) cm(-3) for x <= 5% and T <= 300 K. (C) 2014 Elsevier B.V. All rights reserved.