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arXiv · 2002.06462

Pump induced motion of an interface between competing orders

Abstract

We study the motion of an interface separating two regions with different electronic orders following a short duration pump that drives the system out of equilibrium. Using a generalized Ginzburg-Landau approach and assuming that the main effect of the nonequilibrium drive is to transiently heat the system we address the question of the direction of interface motion; in other words, which ordered region expands and which contracts after the pump. Our analysis includes the effects of differences in free energy landscape and in order parameter dynamics and identifies circumstances in which the drive may act to increase the volume associated with the subdominant order, for example when the subdominant order has a second order free energy landscape while the dominant order has a first order one.

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Zhiyuan Sun, Andrew J. Millis. 2020-02-15. Pump induced motion of an interface between competing orders. https://doi.org/10.1103/physrevb.101.224305

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