Extend fork-tip analysis to spin-triplet and multicomponent superconductors

Extend the fork-tip Josephson STM analysis to spin-triplet superconductors and to realistic band structures containing multi-component superconducting order parameters.

Background

The analysis in the paper focuses on Josephson tunneling between a spin-singlet superconducting tip and a spin-singlet topological superconductor. The authors note that probing spin-triplet superconductors would require a superconducting STM tip with nontrivial pairing, potentially involving a Majorana bound state, because a conventional spin-singlet tip cannot support the relevant coherent pair tunneling.

The paper also uses an idealized setting, including a circular Fermi surface and a relatively simple order-parameter description. Applying the protocol to spin-triplet systems and realistic band structures with multi-component order parameters is identified as an unresolved extension.