The Dressed Bands Of Electron In Semiconductor Driven By Laser Field

In this thesis, we first introduce the atomic optical Stark effect in a classical light field, and then describe some basic theories and methods of electronic bands in semiconductors. In the framework of three-band model and k.p perturbation method, the dressed bands of semiconductors have been investigated using the renormalized effective mass approximation, dressed-band approximation and exact Floquet matrix method. It is demonstrated that quasi-energy calculated from the dressed-band approximation are essentially consistent with that from renormalized effective mass approximation under low field intensity. While the quasienergies from dressed-band approximation and Floquet matrix method show good agreement in the prediction of characteristic points. Moreover, comparing two-band model, some new phenomena are found in our three-band model, i.e., warping, avoided crossing etc.