Antichiral edge states and Bogoliubov Fermi surfaces in a two-dimensional proximity-induced superconductor

TL;DR

This paper demonstrates that a 2D electron gas with Rashba spin-orbit coupling, under a parallel magnetic field and proximity-induced superconductivity, can host a topological phase with antichiral edge states and Bogoliubov Fermi surfaces, revealing unique edge phenomena.

Contribution

It introduces a novel topological phase in a 2D superconductor with Rashba coupling and magnetic field, featuring antichiral edge states and Bogoliubov Fermi surfaces.

Findings

Presence of antichiral edge states localized at sample edges.

Existence of Bogoliubov Fermi surfaces in the topological phase.

Characteristic signatures in Josephson junction current-phase relation.

Abstract

We show that a magnetic field parallel to the plane of a two-dimensional electron gas with Rashba spin orbit coupling in proximity to a superconductor leads to a topological phase in coexistence with a single pair of Bogoliubov Fermi surfaces. This phase hosts antichiral edge states of co-propagating Majorana fermions and are spatially localized at the opposite edges of the sample, perpendicular to the magnetic field. We discuss the characteristic signatures in the current-phase relation of a Josephson junction formed by two reservoirs in the topological phase.