Optical pump-probe time- and magnetic-field-resolved Kerr rotation measurements provide a window into the mechanisms that generate dynamic nuclear polarization in bulk gallium arsenide. Previously, we have reported an unexpected dependence of the direction of the nuclear polarization on the sweep direction of the applied external magnetic field. In this paper, we present numerical calculations based on a model for this nuclear polarization due to the optical orientation and optical Stark effect produced by a train of ultrafast optical pulses. We demonstrate the correspondence of the model to our experimental measurements for different laser wavelengths and magnetic field sweep rates. Finally, we show that the model reproduces the sweep direction dependence and provides an explanation for this behavior.

中文翻译：

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周期性泵浦砷化镓中光学斯塔克效应引起的动态核极化

光泵探针时间分辨和磁场分辨Kerr旋转测量提供了进入在砷化镓镓中产生动态核极化的机制的窗口。以前，我们已经报告了核极化方向对所施加的外部磁场的扫描方向的意外依赖关系。在本文中，由于一系列超快光脉冲产生的光学取向和光学斯塔克效应，我们基于这种核极化模型提出了数值计算方法。我们展示了该模型与我们针对不同激光波长和磁场扫描速率的实验测量值的对应关系。最后，我们表明该模型再现了扫描方向的相关性，并提供了对此行为的解释。