Superconducting and chiral-glass to insulator transition in phase-glass models in a magnetic field.

Superconducting and chiral-glass to insulator transition in phase-glass models in a magnetic field.

Enzo Granato
Instituto Nacional de Pesquisas Espaciais, 12227-010 São José dos Campos, SP, Brazil

We investigate the quantum phase transitions of a two-dimensional phase-glass in an external magnetic field with frustration parameter f. The model describes the effects of gauge disorder in superconductors due to frustration effects of random negative Josephson-junction couplings [1,2]. The phase diagram and critical behavior are obtained from path-integral Monte Carlo simulations at zero temperature. A superconducting chiral-glass phase occurs for sufficiently large disorder, which is insensitive to the additional magnetic-field frustration when f=1/2 and f=1/3. The results are compared with recent measurements on nanohole superconducting thin films, doped with magnetic impurities [3].

[1] P. Phillips and D. Dalidovich, Science 302, 243 (2003).

[2] E. Granato, Phys. Rev. B 102, 184503 (2020).

[3] X. Zhang, J. C. Joy, C. Wu, J. H. Kim, J. Xu, and J. M. Valles Jr, Phys. Rev. Lett. 122, 157002 (2019).