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arXiv · 0708.3504

Anisotropic conductivity of disordered 2DEGs due to spin-orbit interactions

Oleg Chalaev·Daniel Loss
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Abstract

We show that the conductivity tensor of a disordered two-dimensional electron gas becomes anisotropic in the presence of both Rashba and Dresselhaus spin-orbit interactions (SOI). This anisotropy is a mesoscopic effect and vanishes with vanishing charge dephasing time. Using a diagrammatic approach including zero, one, and two-loop diagrams, we show that a consistent calculation needs to go beyond a Boltzmann equation approach. In the absence of charge dephasing and for zero frequency, a finite anisotropy σ_{xy} e^2/lhpf arises even for infinitesimal SOI.

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Oleg Chalaev, Daniel Loss. 2008-03-31. Anisotropic conductivity of disordered 2DEGs due to spin-orbit interactions. https://doi.org/10.1103/physrevb.77.115352

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