arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0801.0255cond-mat.mes-hall
收藏

二维空穴气体中的电流感生自旋极化

Current-induced Spin Polarization in Two-Dimensional Hole Gas

Chao-Xing Liu, Bin Zhou, Shun-Qing Shen, Bang-fen Zhu

摘要:

研究了具有结构反转不对称性的二维空穴气中的电流诱导自旋极化。利用微扰理论,我们重新推导了2DHG的有效$k$ -立方Rashba哈密顿量和相应的广义自旋算符。然后基于线性响应理论,考虑无序效应,对电流诱导自旋极化进行了解析和数值计算。我们发现,与二维电子气不同,在低掺杂区,2DHG中的自旋极化与费米能级成线性关系,并且随着费米能级的增加,自旋极化可能被抑制,甚至改变其符号.我们预测一个明显的峰值自旋极化在2DHG一旦费米能级之间的最低光洞子带的两个自旋分裂分支的最低点。我们讨论了在实验中测量量子阱的温度和宽度的可能性。

英文摘要:

We investigate the current-induced spin polarization in the two-dimensional hole gas (2DHG) with the structure inversion asymmetry. By using the perturbation theory, we re-derive the effective $k$-cubic Rashba Hamiltonian for 2DHG and the generalized spin operators accordingly. Then based on the linear response theory we calculate the current-induced spin polarization both analytically and numerically with the disorder effect considered. We have found that, quite different from the two-dimensional electron gas, the spin polarization in 2DHG depends linearly on Fermi energy in the low doping regime, and with increasing Fermi energy, the spin polarization may be suppressed and even changes its sign. We predict a pronounced peak of the spin polarization in 2DHG once the Fermi level is somewhere between minimum points of two spin-split branches of the lowest light-hole subband. We discuss the possibility of measurements in experiments as regards the temperature and the width of quantum wells.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑