Raising the critical temperature by disorder in unconventional superconductors mediated by spin fluctuations
Abstract
We propose a mechanism whereby disorder can enhance the transition temperature Tc of an unconventional superconductor with pairing driven by exchange of spin fluctuations. The theory is based on a self-consistent real space treatment of pairing in the disordered one-band Hubbard model. It has been demonstrated before that impurities can enhance pairing by softening the spin fluctuations locally; here, we consider the competing effect of pair-breaking by the screened Coulomb potential also present. We show that, depending on the impurity potential strength and proximity to magnetic order, this mechanism results in a weakening of the disorder-dependent Tc-suppression rate expected from Abrikosov-Gor'kov theory, or even in disorder-generated Tc enhancements.
Keywords
Cite
@article{arxiv.1712.07914,
title = {Raising the critical temperature by disorder in unconventional superconductors mediated by spin fluctuations},
author = {Astrid T. Roemer and P. J. Hirschfeld and Brian M. Andersen},
journal= {arXiv preprint arXiv:1712.07914},
year = {2018}
}
Comments
6 pages, 4 figures + Supplementary Material