Disorder-Induced Topological Defects in a d=2 Elastic Medium at Zero Temperature

A. Alan Middleton

doi:10.1103/physrevb.61.14787

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Disorder-Induced Topological Defects in a d=2 Elastic Medium at Zero Temperature

A. Alan Middleton

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Abstract

The density and correlations of topological defects are investigated numerically in a model of a d=2 elastic medium subject to a periodic quenched random potential. The computed density of defects decreases approximately exponentially with the defect core energy. Comparing the defect-free ground state with the ground state with defects, it is found that the difference is described by string-like excitations, bounded by defect pairs, which have a fractal dimension of 1.250(3). At zero temperature, the disorder-induced defects screen the interaction of introduced vortex pairs.

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A. Alan Middleton. 1998-07-28. Disorder-Induced Topological Defects in a d=2 Elastic Medium at Zero Temperature. https://doi.org/10.1103/physrevb.61.14787

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