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Phase Transitions in the Two-Dimensional Random Gauge XY Model

Petter Holme·Petter Minnhagen·Beom Jun Kim
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Abstract

The two-dimensional random gauge \xy model, where the quenched random variables are magnetic bond angles uniformly distributed within $[-rπ, rπ]$ ($0 \leq r \leq 1$), is studied via Monte Carlo simulations. We investigate the phase diagram in the plane of the temperature $T$ and the disorder strength $r$, and infer, in contrast to a prevailing conclusion in many earlier studies, that the system is superconducting at any disorder strength $r$ for sufficiently low $T$. It is also argued that the superconducting to normal transition has different nature at weak disorder and strong disorder: termed Kosterlitz-Thouless (KT) type and non-KT type, respectively. The results are compared to earlier works.

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Petter Holme, Petter Minnhagen, Beom Jun Kim. 2003-01-16. Phase Transitions in the Two-Dimensional Random Gauge XY Model. https://doi.org/10.1103/physrevb.67.104510

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