Anisotropic Electron Transport in Lattice-Mismatch-Strained GalnAs Alloys

Besides Gaxin1_xAs with compositions nearly lattice-matched to GaAs and InP substrates both In-rich and highly strained alloys become increasingly important for heterojunction transistors and emitters also for room temperature applications. Based on deformation potential theory we first express the strain induced shifts of the conduction and valence band edges under biaxial stress. Using k·p theory we calculate the anisotropic effective mass tensor of the direct conduction band minimum. The tetragonal distortion of the cubic crystal results in different masses m11 1 m.l for in-plane and perpendicular directions, respectively.