Josephson Junction of Nodal Superconductors

Monolayer and few-layer transition metal dichalcogenides (TMDs) have been suggested
as a platform to study unconventional superconductivity - both intrinsic and induced. The presence of a
strong Ising spin-orbit coupling in these materials locks the spins perpendicular to the surface resulting
in remarkable stability to an in-plane magnetic field beyond the Pauli limit. When the magnetic field is
increased beyond this limit, a quantum phase transition occurs into a topological nodal-superconducting phase.
This phase is characterized by Majorana flat bands. We use the Bogoliubov-de Gennes (BdG) Hamiltonian formalism
to show that the unique topological properties of this non-trivial phase are reflected in the current across junctions of
such nodal superconductors separated by an insulating barrier. By studying the dependence of the Josephson current on
the phase difference between two sides of the junction, one can infer these topological properties.

Reference: R.Seshadri, M. Khodas, and D. Meidan, https://arxiv.org/abs/2201.11514