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arXiv · 1706.03685

Microscopic Theory of Spin Toroidization in Periodic Crystals

Yang Gao·David Vanderbilt·Di Xiao
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Abstract

Using the semiclassical theory of electron dynamics, we derive a gauge-invariant expression for the spin toroidization in a periodical crystal. We show that the spin toroidization is comprised of two contributions: one is due to the configuration of a classical spin array, while the other comes from the coordinate shift of the electron as spin carrier in response to the inhomogeneous magnetic field. We then establish a direct and elengant relation between our spin toroidization and the antisymmetric magnetoelectric polarizability in insulators. Finally, we demonstrate our spin toroidization in a tight-binding model and show that it is a genuine bulk quantity.

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Yang Gao, David Vanderbilt, Di Xiao. 2018-04-05. Microscopic Theory of Spin Toroidization in Periodic Crystals. https://doi.org/10.1103/physrevb.97.134423

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