We report pressure-induced superconductivity in antiferromagnetic cerium compounds and a ferromagnetic uranium compound, focusing on the relation between the superconducting state and the Fermi surface instability in CeRhIn 5 and the huge upper critical field Hc2 in CeIrSi 3 without inversion symmetry in the crystal structure. The pairing interaction is well correlated with ferromagnetism, as well as antiferromagnetism or antiferromagnetic fluctuations. In the recently discovered superconductor NpPd5Al2, superconductivity is found to be located in the vicinity of an antiferromagnetically ordered state. The upper critical field Hc2 is strongly supressed by the large paramagneic effect, and the corresponding magnetization curve indicates a step-like increase at Hc2, producing a first-order phase transition.
- Unconventional superconductivity
ASJC Scopus subject areas
- Physics and Astronomy(all)