Nodeless s-wave superconductivity in the α-Mn structure type noncentrosymmetric superconductor TaOs: A μSR study

Abstract

Noncentrosymmetric superconductors can lead to a variety of exotic properties in the superconducting state such as line nodes, multigap behavior, and time-reversal symmetry breaking. In this paper, we report the properties of the new noncentrosymmetric superconductor TaOs, using muon spin relaxation and rotation measurements. It is shown using the zero-field muon experiment that TaOs preserve the time-reversal symmetry in the superconducting state. From the transverse field muon measurements, we extract the temperature dependence of $\lambda (T)$ which is proportional to the superfluid density. This data can be fit with a fully gapped s-wave model for $\alpha$ = $\Delta (0)/k_B{T}_c$ = 2.01 $\pm$ 0.02. Furthermore, the value of magnetic penetration depth is found to be 5919 $\pm$ 45 \textÅ, which is consistent with the value obtained from the bulk measurements.

10 pages, 4 figures