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arXiv 2112.04765cond-mat.mes-hall
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近藤关联和自旋轨道耦合对碳纳米管量子点自旋极化输运的影响

Impact of Kondo correlations and spin-orbit coupling on spin-polarized transport in carbon nanotube quantum dot

D. Krychowski, S. Lipiński

摘要:

在有限U从玻色子平均场近似下,利用非平衡格林函数方法讨论了非共线磁化的铁磁电极与量子点耦合的自旋极化输运.电极磁化方向的差异开启了非对角自旋轨道传输,除了纵向极化的自旋电流外,还出现了自旋翻转电流。我们还研究了零偏压下的平衡纯自旋电流,并讨论了它与磁化方向、自旋轨道耦合强度和栅电压的关系。这些因素对隧道磁电阻(TMR)的影响也进行了。一般来说,自旋-轨道耦合会削弱TMR,但它可以改变它的符号。

英文摘要:

Spin polarized transport through a quantum dot coupled to ferromagnetic electrodes with noncollinear magnetizations is discussed in terms of nonequilibrium Green functions formalism in the finite-U slave boson mean field approximation. The difference of orientations of the magnetizations of electrodes opens off-diagonal spin-orbital transmission and apart from spin currents of longitudinal polarization also spin-flip currents appear. We also study equilibrium pure spin current at zero bias and discuss its dependence on magnetization orientation, spin-orbit coupling strength and gate voltage. Impact of these factors on tunneling magnetoresistance (TMR) is also undertaken. In general spin-orbit coupling weakens TMR, but it can change its sign.

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。

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