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arXiv · 1104.1345

Current driven defect unbinding transition in an XY ferromagnet

Aditi Mitra·Andrew J. Millis
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Abstract

A Keldysh-contour effective field theory is derived for magnetic vortices in the presence of current flow. The effect of adiabatic and non-adiabatic spin transfer torques on vortex motion is highlighted. Similarities to and differences from the superconducting case are presented and explained. Current flow across a magnetically ordered state is shown to lead to a defect-unbinding phase transition which is intrinsically nonequilibrium in the sense of not being driven by a variation in effective temperature. The dependence of the density of vortices on the current density is determined.

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Aditi Mitra, Andrew J. Millis. 2011-07-21. Current driven defect unbinding transition in an XY ferromagnet. https://doi.org/10.1103/physrevb.84.054458

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