paper

Large upper critical field in non-centrosymmetric superconductor Y2C3

arXiv:1101.3145 · doi:10.1016/j.jpcs.2010.10.072

Abstract

We determine the upper critical field $I^¼_{0} H_{c 2} (T_{c})$ of non-centrosymmetric superconductor $Y_{2} C_{3}$ using two distinct methods: the bulk magnetization M(T) and the tunnel-diode oscillator (TDO) based impedance measurements. It is found that the upper critical field reaches a value of 30T at zero temperature which is above the weak-coupling Pauli paramagnetic limit. We argue that the observation of such a large $I^¼_{0} H_{c 2} (0)$ in $Y_{2} C_{3}$ could be attributed to the admixture of spin-singlet and spin-triplet pairing states as a result of broken inversion symmetry.

4 pages, 3 figures, accepted by J. Phys. Chem. Solids