Regular Article - Solid State and Materials
Magnetic-field frustration and chiral-glass to insulator transition in superconducting arrays with random junctions
Laboratório Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, 12227-010, São José dos Campos, SP, Brazil
Accepted: 12 July 2021
Published online: 19 July 2021
We study the effects of random Josephson junctions and applied magnetic field on the quantum phase transitions of superconducting arrays, described by a two-dimensional phase-glass model. The zero-temperature phase diagram and critical behavior are obtained from path-integral Monte Carlo simulations. A superconducting chiral-glass phase occurs for sufficiently large disorder resulting from frustration effects of the junctions. Unlike the superconductor–insulator transition for weak disorder, the chiral-glass to insulator transition is insensitive to additional frustration introduced by an external magnetic field corresponding to half flux quantum per plaquette. The results are consistent with recent measurements on superconducting thin films with a periodic pattern of nanoholes in an applied magnetic field and doped with magnetic impurities. The magnetic-field frustration effects for the activation energy at low doping and its disappearance at higher doping, observed experimentally, is indicative of a transition to the chiral-glass regime.
© The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature 2021