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arXiv · 1808.00094

Monte Carlo simulations of a disordered superconductor-metal quantum phase transition

Ahmed K. Ibrahim·Thomas Vojta
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Abstract

We investigate the quantum phase transitions of a disordered nanowire from superconducting to metallic behavior by employing extensive Monte Carlo simulations. To this end, we map the quantum action onto a (1+1)-dimensional classical XY model with long-range interactions in imaginary time. We then analyze the finite-size scaling behavior of the order parameter susceptibility, the correlation time, the superfluid density, and the compressibility. We find strong numerical evidence for the critical behavior to be of infinite-randomness type and to belong to the random transverse-field Ising universality class, as predicted by a recent strong disorder renormalization group calculation.

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Ahmed K. Ibrahim, Thomas Vojta. 2018-12-29. Monte Carlo simulations of a disordered superconductor-metal quantum phase transition. https://doi.org/10.1140/epjb%2Fe2018-90497-5

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