Fully gapped superconducting state in Au2Pb: A natural candidate for topological superconductor. (16th February 2017)

• Record Type: Journal Article
• Authors: Yu, Y. J.; Xu, Y.; Xing, Y.; Zhang, J.; Ying, T. P.; Hong, X. C.; Wang, M. X.; Zhang, X.; Jia, S.; Wang, J.; Li, S. Y.
• Is Part Of: Europhysics letters. Volume 116:Number 6(2016:Dec.)
• Publication Date: 2017-02-16
• Subjects: 74.25.Bt -- 74.25.fc; Physics -- Periodicals; Electronic journals; 530.05
• DOI: 10.1209/0295-5075/116/67002
• Languages: English
• ISSNs: 0295-5075

Abstract

Abstract: We measured the ultra-low-temperature specific heat and thermal conductivity of the Au2 Pb single crystal, a possible three-dimensional Dirac semimetal with a superconducting transition temperature . The electronic specific heat can be fitted by a two-band s -wave model, which gives the gap amplitudes Δ1 (0)/ k B T c = 1.41 and Δ2 (0)/ k B T c = 5.25. From the thermal conductivity measurements, a negligible residual linear term in zero field and a slow field dependence of at low field are obtained. These results suggest that Au2 Pb has a fully gapped superconducting state in the bulk, which is a necessary condition for topological superconductors if Au2 Pb is indeed one.