Unconventional superconducting pairing in a B20 Kramers Weyl semimetal

TL;DR

This paper predicts that the chiral metal RhGe exhibits nontrivial superconductivity with potential topological properties, driven by its unique Weyl fermions and Fermi arc states, making it a promising candidate for topological superconductors.

Contribution

It introduces RhGe as a new material candidate for topological superconductivity with detailed analysis of its unconventional pairing mechanisms.

Findings

RhGe has a transition temperature of 5.8 K.

Supports multiple type-II van Hove singularities.

Indicates presence of nontrivial superconducting pairing.

Abstract

Topological superconductors present an ideal platform for exploring nontrivial superconductivity and realizing Majorana boundary modes in materials. However, finding a single-phase topological material with nontrivial superconducting states is a challenge. Here, we predict nontrivial superconductivity in the pristine chiral metal RhGe with a transition temperature of 5.8 K. Chiral symmetries in RhGe enforce multifold Weyl fermions at high-symmetry momentum points and spin-polarized Fermi arc states that span the whole surface Brillouin zone. These bulk and surface chiral states support multiple type-II van Hove singularities that enhance superconductivity in RhGe. Our detailed analysis of superconducting pairing symmetries involving Chiral Fermi pockets in RhGe, indicates the presence of nontrivial superconducting pairing. Our study establishes RhGe as a promising candidate material for hosting mixed-parity pairing and topological superconductivity.