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arXiv · 0709.0203

Enhancement of polarization in a spin-orbit coupling quantum wire with a constriction

Jun-Feng Liu·Zhi-Cheng Zhong·Lei Chen·Dingping Li·Chao Zhang·Zhongshui Ma
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Abstract

We investigate the enhancement of spin polarization in a quantum wire in the presence of a constriction and a spin-orbit coupling segment. It is shown that the spin-filtering effect is significantly heightened in comparison with the configuration without the constriction. It is understood in the studies that the constriction structure plays a critical role in enhancing the spin filtering by means of confining the incident electrons to occupy one channel only while the outgoing electrons occupy two channels. The enhancement of spin-filtering has also been analyzed within the perturbation theory. Because the spin polarization arises mainly from the scattering between the constriction and the segment with spin-orbit coupling, the sub-band mixing induced by spin-orbit interaction in the scattering process and the interferences result in higher spin-filtering effect.

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Jun-Feng Liu, Zhi-Cheng Zhong, Lei Chen, Dingping Li, Chao Zhang, Zhongshui Ma. 2007-09-03. Enhancement of polarization in a spin-orbit coupling quantum wire with a constriction. https://doi.org/10.1103/physrevb.76.195304

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