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Permanent current from non-commutative spin algebra

Gen Tatara·Hiroshi Kohno
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Abstract

We show that a spontaneous electric current is induced in a nano-scale conducting ring just by putting three ferromagnets. The current is a direct consequence of the non-commutativity of the spin algebra, and is proportional to the non-coplanarity (chirality) of the magnetization vectors. The spontaneous current gives a natural explanation to the chirality-driven anomalous Hall effect.

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Gen Tatara, Hiroshi Kohno. 2002-08-20. Permanent current from non-commutative spin algebra. https://doi.org/10.1103/physrevb.67.113316

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