Jeudi 05 novembre 2015 à 10h15
Salle MaNEP, Ecole de Physique

Superconductivity in Weyl metals

Alexander Zyuzin, Université de Bâle

We report on a study of intrinsic superconductivity in a Weyl metal, i.e., a doped Weyl semimetal. We find that, in an inversion-symmetric Weyl metal, the odd-parity BCS state has a lower energy than the FFLO state, despite the nodes in the gap. The FFLO state, on the other hand, may have a lower energy in a noncentrosymmetric Weyl metal, in which Weyl nodes of opposite chirality have different energy. However, realizing the FFLO state is, in general, very difficult since the paired states are not related by any exact symmetry, which precludes a weak-coupling superconducting instability. We also discuss some of the physical properties of the nodal BCS state, in particular, Majorana and Fermi arc surface states.