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What are spin currents in Heisenberg magnets?

Florian Schuetz·Peter Kopietz·Marcus Kollar
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Abstract

We discuss the proper definition of the spin current operator in Heisenberg magnets subject to inhomogeneous magnetic fields. We argue that only the component of the naive "current operator" J_ij S_i x S_j in the plane spanned by the local order parameters and is related to real transport of magnetization. Within a mean field approximation or in the classical ground state the spin current therefore vanishes. Thus, finite spin currents are a direct manifestation of quantum correlations in the system.

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Florian Schuetz, Peter Kopietz, Marcus Kollar. 2004-11-16. What are spin currents in Heisenberg magnets?. https://doi.org/10.1140/epjb%2Fe2004-00348-9

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