Spin conductance switch effects in Rashba-Dresselhaus quantum wire with two step-likes

Abstract

Abstract: The electron spin conductance switch effect in a two step-likes quantum wire under modulation of both the Rashba and Dresselhaus spin-orbit couplings (SOCs) is studied by using the non-equilibrium Green's function (NEGF) method with tight binding approximation scheme. It shows that a very large spin conductance occurs in the consideration system when the electrons transport in the forward biased case, while the spin conductance vanishes when the electrons transport in the backward biased case. Interestingly, the results show that the spin conductance of the system displays a "circular" profile versus both the Rashba and Dresselhaus SOCs, which it demonstrate that the two SOCs have the same role on inducing spin conductance. Therefore, one can control the spin conductance of the system by tuning either the Rashba or Dresselhaus SOC strengths, thus making the proposed quantum wire an all-electrical spin conductance diode in future.

Key words: electronic transport, spin conductance switch effects, non-equilibrium Green's function method, two step-likes quantum wire, Rashba and Dresselhaus spin-orbit couplings

XU Zhonghui, HONG Zhaohai, LUO Bing, HUANG Jinsong, WANG Xiaohui. Spin conductance switch effects in Rashba-Dresselhaus quantum wire with two step-likes[J]. Chinese Journal of Quantum Electronics, 2020, 37(1): 99-109.

References

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