Evidence for charged critical behavior in the pyrochlore superconductor RbOs2O6

TL;DR

This study provides evidence that charged critical fluctuations dominate the superconducting transition in RbOs2O6, contrasting with mean-field and uncharged behaviors seen in other superconductors, aligning with theoretical predictions for charged criticality.

Contribution

It presents experimental evidence for charged critical behavior in a pyrochlore superconductor, supporting theoretical models of charged criticality in superconducting phase transitions.

Findings

Charged critical fluctuations dominate near Tc in RbOs2O6

Contrasts with mean-field behavior in conventional superconductors

Aligns with theoretical predictions for charged criticality

Abstract

We analyze magnetic penetration depth data of the recently discovered superconducting pyrochlore oxide RbOs2O6. Our results strongly suggest that in RbOs2O6 charged critical fuctuations dominate the temperature dependence of the magnetic penetration depth near Tc. This is in contrast to the mean-field behavior observed in conventional superconductors and the uncharged critical behavior found in nearly optimally doped cuprate superconductors. However, this finding agrees with the theoretical predictions for charged criticality and the charged criticality observed in underdoped YBa2Cu3O6.59.