Order parameter symmetry and mode coupling effects at dirty superconducting quantum phase transitions
Abstract
We derive an order-parameter field theory for a quantum phase transition between a disordered metal and an exotic (non-s-wave) superconductor. Mode coupling effects between the order parameter and other fermionic soft modes lead to an effective long-range interaction between the anomalous density fluctuations which is reflected in singularities in the free energy functional. However, this long-range interaction is not strong enough to suppress disorder fluctuations. The asymptotic critical region is characterized by run-away flow to large disorder. For weak coupling, this asymptotic region is very narrow. It is preempted by a wide crossover regime with mean-field critical behavior and, in the p-wave case, logarithmic corrections to scaling in all dimensions.
Cite
@article{arxiv.cond-mat/0211519,
title = {Order parameter symmetry and mode coupling effects at dirty superconducting quantum phase transitions},
author = {Rastko Sknepnek and Thomas Vojta and Rajesh Narayanan},
journal= {arXiv preprint arXiv:cond-mat/0211519},
year = {2009}
}
Comments
final version as published