Highly Repetitive Picosecond Polarization Switching in Type-II AlGaAs/AlAs Multiple Quantum Well Structures

Abstract
We have demonstrated highly repetitive picosecond polarization optical switching operation of type-II quantum well structures at room temperature. The switching mechanism is due to the fast Γ-X interlayer scattering of electrons and the fast spin relaxation of holes. According to our experimental results, the switching time is less than 1 ps, the switching power is as low as 3 nJ/cm2, and the switching repetition rate is more than 80 GHz. Moreover we point out the possibility of continuous optical switching operation for future applications.