半导体中相干控制光电流对光场的偏振依赖性

采用黄金定则方法和Kane六能带模型，分析了半导体中的量子干涉控制光生电流效应.计算了不同偏振光场下载流子在动量空间的初始布居分布，从微观上阐明了相干电流对光场的偏振依赖特性.在平行线偏振情况下，相干电流方向沿光场的偏振方向；而在正交线偏振情况下，电流方向与倍频光的偏振方向相同.还证明了只有当单光子跃迁和双光子跃迁相平衡时才能获得最大的电流注入效率. 关键词： 量子干涉 光电流 线偏振光

Polarization effects of coherent control photocurrent in semiconductors

Quantum interference control photocurrent in bulk semiconductors is analyzed using the Fermi golden rule and Kane six-band model. The initial momentum distributions of photoexcited carriers in different polarized light fields are calculated. The polarization dependence of the coherent currents is shown explicitly in a microscopic level. For the case of parallel linear polarizations, the current direction is along the direction of the light polarization; while for the case of perpendicular polarizations the current direction is along the polarization of the harmonic frequency light. It is also shown that when the one-photon transition and the two-photon transition is balanced, the maximum current injection efficiency is achieved.