Non-local transport signatures of topological superconductivity in a phase-biased planar Josephson junction

TL;DR

This paper theoretically investigates how non-local conductance measurements in phase-biased planar Josephson junctions can detect topological superconductivity, highlighting the role of phase difference tunability and Zeeman interaction effects.

Contribution

It introduces a method to identify topological transitions through non-local conductance sign changes, considering the influence of Zeeman interaction on phase diagrams.

Findings

Non-local conductance sign change indicates topological transition.

Zeeman interaction significantly alters the phase diagram.

Phase bias tunability affects detection of topological states.

Abstract

Hybrid Josephson junctions realized on a two-dimensional electron gas are considered promising candidates for developing topological elements that are easily controllable and scalable. Here, we theoretically study the possibility of the detection of topological superconductivity via the non-local spectroscopy technique. We show that the non-local conductance is related to the system band structure, allowing probe of the gap closing and reopening related to the topological transition. We demonstrate that the topological transition induces a change in the sign of the non-local conductance at zero energy due to the change in the quasiparticle character of the dispersion at zero momentum. Importantly, we find that the tunability of the superconducting phase difference via flux in hybrid Josephson junctions systems is strongly influenced by the strength of the Zeeman interaction, which leads to considerable modifications in the complete phase diagram that can be measured under realistic experimental conditions.