Spin-drift transport in semiconductors
Spin-drift transport in semiconductors
复制标题
半导体中的自旋漂移输运
DOI：
10.1088/0022-3727/41/3/035105
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
M. I. Miah
中科院分区：
文献类型：
--
作者：
M. I. Miah
本文研究了外加电场下半导体中的自旋输运。我们的实验检测光注入电子自旋和他们的弛豫漂移输运在本征和适度n掺杂GaAs，基于非凡的霍尔（eH）效应。对于相对较低的电场（E），光学自旋诱导的eH效应在n型掺杂的GaAs被发现是增强的掺杂浓度，而不是依赖于E，这表明大量的光学自旋极化在这些非本征半导体漂移输运过程中被保存。然而，当自旋取向的电子被注入高E时，由于热电子的自旋进动频率的增加，在eH电压（VeH）中观察到非常显著的降低。计算了D 'yakonov-Perel'机制下的自旋弛豫，认为这是高E下超热电子自旋弛豫如此迅速的原因。然而，在本征GaAs（i-GaAs）中，观察到弱得多的VeH，并且由于i-GaAs中的库仑相互作用，电子自旋被空穴散射，因此考虑了Bir-Aronov-Pikus机制的自旋弛豫。讨论了斜散射和侧跳作为光自旋诱导横向霍尔电流的可能机制。基于自旋漂移-扩散模型，研究了漂移和扩散对VeH的贡献。与理论研究结果进行了比较。
We present a study on spin transport in semiconductors under applied electric fields. Our experiments detect photoinjected electron spins and their relaxation during drift transport in intrinsic and moderately n-doped GaAs, based on the extraordinary Hall (eH) effect. For relatively low electric field (E), the optically spin-induced eH effect in n-doped GaAs is found to be enhanced with increasing doping density and not to depend much on E, indicating that a substantial amount of optical spin polarization is preserved during the drift transport in these extrinsic semiconductors. However, when the spin-oriented electrons are injected with a high E, a very significant decrease is observed in the eH voltage (VeH) due to an increase in the spin precession frequency of the hot electrons. Spin relaxation by the D'yakonov-Perel' mechanism is calculated, and is suggested to be the reason for such a rapid spin relaxation for hot electrons under a high E. However, in an intrinsic GaAs (i-GaAs), a much weaker VeH is observed and, as the electron spins scattered by holes due to the Coulomb interaction in i-GaAs, the spin relaxation by the Bir-Aronov–Pikus mechanism is considered. Skew scattering and side jump as possible mechanisms of the optically spin-induced transverse Hall currents are discussed. Based on a spin drift–diffusion model, drift and diffusion contributions to the VeH are examined. The results are also discussed in comparison with theoretical investigations.
影响因子：
8.6
作者：
Kikkawa, JM;Awschalom, DD
通讯作者：
Awschalom, DD