The magnetic penetration depth λ(T) and the upper critical field μ0Hc2(Tc) of the non-centrosymmetric superconductor Y2C3 have been measured using a tunnel-diode-based resonant oscillation technique. We found that the penetration depth λ(T) and its corresponding superfluid density ρs(T) show linear temperature dependence at very low temperatures (TTc), indicating the existence of line nodes in the superconducting energy gap. Moreover, the upper critical field μ0Hc2(Tc) presents a weak upturn at low temperatures with a rather high value of μ0Hc2(0) 29 T, which slightly exceeds the weak-coupling Pauli limit. We discuss the possible origins for these nontrivial superconducting properties, and argue that the nodal gap structure in Y 2C3 is likely attributed to the absence of inversion symmetry, which allows the admixture of spin-singlet and spin-triplet pairing states.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Apr 29 2011|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics