Majorana fermion arcs and the local density of states of UTe$_2$

TL;DR

This paper investigates the surface states and local density of states in UTe$_2$, a candidate chiral p-wave superconductor, highlighting the effects of spin-orbit coupling and symmetry breaking on Majorana fermions.

Contribution

It provides a theoretical analysis of Majorana fermion arcs and particle-hole symmetry breaking in UTe$_2$, incorporating Rashba spin-orbit coupling effects.

Findings

Surface states exhibit Majorana fermion arcs.

Symmetry breaking induces triplet pair density wave.

Broken particle-hole symmetry explained by surface effects.

Abstract

$\text{UTe}_2$ is a leading candidate for chiral p-wave superconductivity, and for hosting exotic Majorana fermion quasiparticles. Motivated by recent STM experiments in this system, we study particle-hole symmetry breaking in chiral p-wave superconductors. We compute the local density of states from Majorana fermion surface states in the presence of Rashba surface spin-orbit coupling, which is expected to be sizeable in heavy-fermion materials like UTe$_2$. We show that time-reversal and surface reflection symmetry breaking lead to a natural pairing tendency towards a triplet pair density wave state, which naturally can account for broken particle-hole symmetry.