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On A Proper Definition of Spin Current

Junren Shi·Ping Zhang·Di Xiao·Qian Niu
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Abstract

The conventional definition of spin current is incomplete and unphysical in describing spin transport in systems with spin-orbit coupling. A proper and measurable spin current is established in this study, which fits well into the standard framework of near-equilibrium transport theory and has the desirable property to vanish in insulators with localized orbitals. Experimental implications of our theory are discussed.

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Junren Shi, Ping Zhang, Di Xiao, Qian Niu. 2006-02-27. On A Proper Definition of Spin Current. https://doi.org/10.1103/physrevlett.96.076604

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