Time-dependent Green's function approach to spin transport assisted by nonclassical light

Abstract

The generation of spin current is of significant importance for advanced spintronic applications. In conventional theory and experiment, microwave sources are usually described by a classical time-varying field in which all fluctuations are neglected. Here, we study the spin current driven by nonclassical light by developing a Green's function method in which both effects of nonclassical light and electron-related interaction can be taken into account. Our theoretical method has more advantages than the linear response theory developed recently as it can be easily extended to the electronic transport problem with interaction. As an example, we calculate the spin current due to the rotating magnetic field in the presence of nonclassical light. It is found that the spin current is sensitive to the state of nonclassical light. Under certain conditions, the transmission and spin current can be smaller than the classical limit, which cannot be broken by a pure classical microwave field. The method developed here and the results reported here will be important for understanding complicated physical phenomena occurring in the hybrid field of spintronics and circuit quantum electrodynamics.