Spin-Dependent Luminescence Enhanced by Interface Stress between III–V Alloy Layers on Excitation of Circularly Polarized Light

Abstract

The relation between the luminescence polarization for circularly polarized light and the band structure of zincblende semiconductor under two-dimensional stress is theoretically discussed. Two type of samples with an unstrained InP layer and a strained InP layer due to the lattice mismatch are prepared. The luminescence from the InP layer excited by circularly polarized light is analyzed using a Babinet-Soleil compensator, (or phase-modulator) and polarizer. The large luminescence polarization of circularly polarized light is observed in the strained sample. At temperatures below 60 K, the luminescence polarization exceeds 25% which is the maximum value predicted in the unstrained crystal. The experimental results show that the luminescence polarization is increased by the internal strain due to the lattice mismatch.