4π Josephson currents in junctions of hybridized multiband superconductors

Abstract

We study two-band one-dimensional superconducting chains of spinless fermions with inter- and intraband pairing. These bands hybridize and, depending on the relative angular momentum of their orbitals, the hybridization can be symmetric or antisymmetric. The self-consistent competition between intra- and interband superconductivity and how it is affected by the symmetry of the hybridization is investigated. In the case of antisymmetric hybridization the intra- and interband pairings do not coexist, while in the symmetric case they do coexist and the interband pairing is shown to be dominant. The topological properties of the model are obtained through the topological invariant winding number and the presence of edge states. We find the existence of a topological phase due to the interband superconductivity and induced by symmetric hybridization. In this case we find a characteristic 4π-periodic Josephson current. In the case of antisymmetric hybridization we also find a 4π-periodic Josephson current in the gapless interband superconducting phase, recently identified to be of Weyl type.

Source-reported materials — not catalogue approval

Similar papers