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s-Wave superconductivity in non-centrosymmetric Re_3W probed by magnetic penetration depth

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 نشر من قبل Yuri Zuev
 تاريخ النشر 2007
  مجال البحث فيزياء
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We report measurements of the temperature dependence of the magnetic penetration depth lambda(T) in non-centrosymmetric superconductor Re_3W. We employed two experimental techniques: extraction of lambda(T) from magnetic {em dc}-susceptibility, measured on a powder sample, and the rf tunnel diode resonator technique, where a bulk polycrystalline sample was used. The results of both techniques agree: the temperature dependence of the penetration depth can be well described by weak-coupling, dirty-limit, s-wave BCS theory where we obtain $Delta(0)/k_BT_C=1.76$. No evidence for unconventional pairing resulting from the absence of the inversion symmetry is found.



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