# $\mu$SR study of noncentrosymmetric superconductor PbTaSe$_2$

## TL;DR

This study uses muon spin rotation to analyze the superconducting properties of PbTaSe$_2$, revealing a conventional multi-band s-wave superconductor with no evidence of time reversal symmetry breaking.

## Contribution

First muon spin rotation study of PbTaSe$_2$ confirming it as a conventional multi-band s-wave superconductor without time reversal symmetry breaking.

## Key findings

- Superfluid density fits a two-band fully gapped model
- No evidence of time reversal symmetry breaking in zero field
- PbTaSe$_2$ exhibits conventional BCS s-wave superconductivity

## Abstract

We present muon spin rotation ($\mu$SR) measurements on the noncentrosymmetric superconductor PbTaSe$_2$. From measurements in an applied transverse field between $H_{c1}$ and $H_{c2}$, we extract the superfluid density as a function of temperature in the vortex state. This data can be fit with a fully gapped two-band model, consistent with previous evidence from ARPES, thermal conductivity, and resistivity. Furthermore, zero field measurements show no evidence for a time reversal symmetry breaking field greater than 0.05~G in the superconducting state. This makes exotic fully gapped spin-triplet states unlikely, and hence we contend that PbTaSe$_2$ is characterized by conventional BCS s-wave superconductivity in multiple bands.