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Nodeless s-wave superconductivity in the {alpha}-Mn structure type noncentrosymmetric superconductor TaOs: A {mu}SR study

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 نشر من قبل Ravi Singh
 تاريخ النشر 2019
  مجال البحث فيزياء
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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 text{AA}, which is consistent with the value obtained from the bulk measurements.

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