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Dislocations and the enhancement of superconductivity in odd-parity superconductor Sr$_2$RuO$_4$

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 نشر من قبل Yiqun Ying
 تاريخ النشر 2012
  مجال البحث فيزياء
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We report observation of the enhancement of superconductivity near lattice dislocations and the absence of the strengthening of vortex pinning in odd-parity superconductor Sr$_2$RuO$_4$, both surprising results in direct contrast to the well known sensitivity of superconductivity in Sr$_2$RuO$_4$ to disorder. The enhanced superconductivity appears to be related fundamentally to the two-component nature of the superconducting order parameter, as revealed in our phenomenological theory taking into account the effect of symmetry reduction near a dislocation.



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