Structural and electronic properties of GaAs0.64P0.19Sb0.17 on GaAs
GaAsPSb is an alloy with strong structural disorder, resulting from internal bond distortion. In this work, we study the structural and electronic properties of GaAs0.64P0.19Sb0.17 grown on GaAs. Results from reciprocal space mapping measurement reveal an unusual large residual strain left in the epilayer. We used the strain and the crystal field splitting determined from piezoreflectance (PzR) to obtain a shear deformation potential b = −1.31 eV. The unstrained energy gap Eg and spin-orbital splitting Δ0 determined from PzR at 300 K are 1.256 eV and 0.442 eV, respectively. The Δ0 of the GaAs0.64P0.19Sb0.17 is higher than that from the linear interpolation of the values of the end-point binaries, 0.363 eV, suggesting that the spin-orbit splitting has a significant negative bowing.