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arXiv · 0802.1350

Equilibrium spin currents: Non-Abelian gauge invariance and color diamagnetism in condensed matter

I. V. Tokatly
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Abstract

The spin-orbit (SO) interaction in condensed matter can be described in terms of a non-Abelian potential known in high-energy physics as a color field. I show that a magnetic component of this color field inevitably generates diamagnetic color currents which are just the equilibrium spin currents discussed in a condensed matter context. These dissipationless spin currents thus represent a universal property of systems with SO interaction. In semiconductors with linear SO coupling the spin currents are related to the effective non-Abelian field via Yang-Mills magnetostatics equation.

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I. V. Tokatly. 2008-02-10. Equilibrium spin currents: Non-Abelian gauge invariance and color diamagnetism in condensed matter. https://doi.org/10.1103/physrevlett.101.106601

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