Optical injection of spin current in direct bandgap GeSn

Abstract

Recent progress in the development of direct band gap GeSn is exploited to investigate the optical injection and coherent control of spin currents in this group IV semiconductor. The analysis of these properties could provide essential information for future innovative optical photon-to-spin conversion interfaces, long-sought after for entanglement distribution. A 30-band k•p model is used to evaluate the electronic properties in the material for a relatively wide range of energies, and a linear tetrahedron method is employed for the Brillouin zone integrations. Carrier, spin, current, and spin current injection rates are calculated for a bichromatic field of frequencies ω and 2ω.