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Topological Defects in the Random-Field XY Model and Randomly Pinned Vortex Lattices

Michel J. P. Gingras·David A. Huse
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Abstract

As a simplified model of randomly pinned vortex lattices or charge-density waves, we study the random-field XY model on square ($d=2$) and simple cubic ($d=3$) lattices. We argue, and confirm in simulations, that the spacing between topological defects (vortices) diverges more strongly than the Imry-Ma pinning length as the random field strength, $H$, is reduced. For $d=3$ the data are consistent with a topological phase transition at a nonzero $H_c$ to a vortex-free pinned phase.

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Michel J. P. Gingras, David A. Huse. 1995-02-06. Topological Defects in the Random-Field XY Model and Randomly Pinned Vortex Lattices. https://doi.org/10.1103/physrevb.53.15193

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