The influence of the Majorana non-locality on the supercurrent

TL;DR

This paper investigates how the non-local nature of Majorana bound states influences the supercurrent in a Josephson junction, revealing that non-locality enables a finite supercurrent and depends on spin canting angles.

Contribution

It analytically and numerically demonstrates that Majorana non-locality allows supercurrent flow and links it to spin canting angles, providing a new way to probe Majorana states.

Findings

Finite supercurrent enabled by Majorana non-locality

Critical current depends on spin canting angle difference

Method to extract Majorana features from experimental data

Abstract

We study the equilibrium Josephson current between an s-wave superconductor and a topological superconducting nanowire with Majorana bound states (MBS) at its ends. Within a low-energy model we show analytically that the non-locality of the MBS allows for a finite supercurrent to flow that otherwise would vanish. In particular, we find the critical current to be a function of the difference in the spin canting angles of the Majorana wave functions at the location of the tunnel contact. We complement our analytical calculations by numerically solving the full tight binding model and show how to extract the main features of the low-energy model from the critical current using available experimental techniques.