标题： 单轴应变对立方半导体中光学自旋取向的影响 显示英文标题

标题： Effect of a uniaxial strain on optical spin orientation in cubic semiconductors

摘要： 单轴应变对立方半导体光学自旋取向的影响是通过计算价带波函数、近共振光激发时来自重空穴和轻空穴能级的光学振子强度以及初始电子自旋极化来研究的。 沿[001]、[111]或[-110]晶体方向的应变以及与应变平行或垂直的圆偏振光激发被考虑。 对于所有这些情况，导带电子总自旋极化具有普遍性，因为i) 振子强度不依赖于应变的大小，而只依赖于其符号。 ii) 虽然振子强度强烈依赖于配置，但由σ+光激发引起的来自重空穴和轻空穴能级的光学跃迁所产生的导带电子自旋极化在所有情况下都等于-0.5，这与简单的原子模型预测一致。 iii) 由重空穴和轻空穴能级的光激发产生的自旋极化不依赖于变形张量和价带变形势，除了沿[-110]方向的应变。 显示英文摘要

摘要： The effect of a uniaxial strain on the optical spin orientation of a cubic semiconductor is investigated by calculating the valence wavefunctions, the optical oscillator strengths and the initial electron spin polarization for near resonant light excitation from heavy and light valence levels. A strain orientation along the [001], [111] or [-110] crystal direction and a circularly-polarized light excitation parallel or perpendicular to the strain are considered. For all these cases, the total conduction electron spin polarization has a universal character since i) the oscillator strengths do not depend on the magnitude of the strain but only on its sign. ii) Although the oscillator strengths strongly depend on the configuration, the conduction electron spin polarization generated by optical transitions from both the heavy and light valence levels induced by sigma + light excitation is in all cases equal to -0.5 as predicted by the simple atomic model. iii) The spin polarization generated by light excitation from heavy and light valence levels does not depend on the deformation tensor and on the valence deformation potential, except for a strain along [-110].