Ultrafast Electrical Control Of Optical Polarization In Hybrid Semiconductor Structure

We theoretically analyze the dynamics of circular polarized photoluminescence (PL) associated with split-off states emerging in a semiconductor quantum well (QW) due to tunnel coupling with remote spin-split bound states. A mechanism for ultrafast PL polarization switching is proposed based on tunnel barrier transparency modulation. Such modulation can be experimentally realized by applying a gate voltage to the semiconductor heterostructure. The proposed mechanism is based on the split-off state energy level position being sensitive to the transparency of the tunnel barrier. The obtained results open the possibility to form fully polarized PL signal and are promising for applications in spintronics, in particular, for ultrafast polarization modulation in spin lasers.