# Majorana Bound States in Double Nanowires with Reduced Zeeman Thresholds due to Supercurrents

## TL;DR

This paper investigates how supercurrents in double nanowire systems with strong spin-orbit coupling can lower the magnetic field thresholds needed to achieve Majorana bound states, enabling topological phases at weaker fields.

## Contribution

It introduces a model showing supercurrents reduce the Zeeman energy and pairing thresholds for topological phases in double nanowires, even with weaker crossed Andreev pairing.

## Key findings

- Supercurrents lower the critical Zeeman energy for topological phases.
- Weak magnetic fields can induce topological states due to supercurrents.
- Topological phases are achievable even with small crossed Andreev pairing.

## Abstract

We study the topological phase diagram of a setup composed of two nanowires with strong Rashba spin-orbit interaction subjected to an external magnetic field and brought into the proximity to a bulk $s$-wave superconductor in the presence of a supercurrent flowing through it. The supercurrent reduces the critical values of the Zeeman energy and crossed Andreev superconducting pairing required to reach the topological phase characterized by the presence of one Majorana bound state localized at each system end. We demonstrate that, even in the regime of the crossed Andreev pairing being smaller than the direct proximity pairing, a relatively weak magnetic field drives the system into the topological phase due to the presence of the supercurrent.