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Variation of shear moduli across superconducting phase transitions

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 نشر من قبل Indranil Paul
 تاريخ النشر 2019
  مجال البحث فيزياء
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We study how shear moduli of a correlated metal change across superconducting phase transitions. Using a microscopic theory we explain why for most classes of superconductors this change is small. The Fe-based and the A15 systems are notable exceptions where the change is boosted by five orders of magnitude. We show that this boost is a consequence of enhanced nematic correlation. The theory explains the unusual temperature dependence of the orthorhombic shear and the back-bending of the nematic transition line in the superconducting phase of the Fe-based systems.

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