Shear modulus anomaly of multi-conponent superconductor: the case of M_x Bi₂Se₃

Abstract

A pair of split superconducting transitions in the presence of a symmetry breaking field is a very definitive signature of multi-component superconductivity[1, 2]. We theoretically study the shear modulus anomaly across such pair of split transitions[3]. The talk will be focused on MxBi2Se3, a nematic superconductor candidate, for which no experimental confirmation of the split transition has been made so far. We propose that the shear modulus C 66 must vanish at the lower transition: a very clear signature detectable by experiments. The observation of shear modulus anomalies would be a conclusive test for the nematic superconductivity hosted by the material.