Spatiotemporal spin fluctuations caused by spin-orbit-coupled Brownian motion

A. V. Poshakinskiy; S. A. Tarasenko

doi:10.1103/physrevb.92.045308

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arXiv · 1505.03826

Spatiotemporal spin fluctuations caused by spin-orbit-coupled Brownian motion

A. V. Poshakinskiy·S. A. Tarasenko

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Abstract

We develop a theory of thermal fluctuations of spin density emerging in a two-dimensional electron gas. The spin fluctuations probed at spatially separated spots of the sample are correlated due to Brownian motion of electrons and spin-obit coupling. We calculate the spatiotemporal correlation functions of the spin density for both ballistic and diffusive transport of electrons and analyze them for different types of spin-orbit interaction including the isotropic Rashba model and persistent spin helix regime. The measurement of spatial spin fluctuations provides direct access to the parameters of spin-orbit coupling and spin transport in conditions close to the thermal equilibrium.

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A. V. Poshakinskiy, S. A. Tarasenko. 2015-05-14. Spatiotemporal spin fluctuations caused by spin-orbit-coupled Brownian motion. https://doi.org/10.1103/physrevb.92.045308

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