Two-gap time reversal symmetry breaking superconductivity in noncentrosymmetric LaNiC2

Shyam Sundar; S. R. Dunsiger; S. Gheidi; K. S. Akella; A. M. Côté; H. U. Özdemir; N. R. Lee-Hone; D. M. Broun; E. Mun; F. Honda; Y. J. Sato; T. Koizumi; R. Settai; Y. Hirose; I. Bonalde; J. E. Sonier

doi:10.1103/PhysRevB.103.014511

Two-gap time reversal symmetry breaking superconductivity in noncentrosymmetric LaNiC2

Shyam Sundar, S. R. Dunsiger, S. Gheidi, K. S. Akella, A. M. Côté, H. U. Özdemir, N. R. Lee-Hone, D. M. Broun, E. Mun, F. Honda, Y. J. Sato, T. Koizumi, R. Settai, Y. Hirose, I. Bonalde, J. E. Sonier

DOI 10.1103/PhysRevB.103.014511 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We report a μSR investigation of a noncentrosymmetric superconductor (LaNiC2) in single-crystal form. Compared to previous μSR studies of noncentrosymmetric superconducting polycrystalline and powder samples, the unambiguous orientation of single crystals enables a simultaneous determination of the absolute value of the magnetic penetration depth and the vortex core size from measurements that probe the magnetic field distribution in the vortex state. The magnetic field dependence of these quantities unambiguously demonstrates the presence of two nodeless superconducting energy gaps. In addition, we detect weak internal magnetic fields in the superconducting phase, confirming earlier μSR evidence for a time-reversal symmetry-breaking superconducting state. Our results suggest that Cooper pairing in LaNiC2 is characterized by an interorbital equal-spin pairing model introduced to unify the pairing states of LaNiC2 and the centrosymmetric superconductor LaNiGa2.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
LaNiC2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	2.7	Pressure unresolved	unknown
LaNiC2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	2.7	Pressure unresolved	unknown
LaNiGa2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
NbSe2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
UPt3 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Sr2RuO4 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
PrOs4Sb12 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown