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Inversion symmetry of Josephson current as test of chiral domain wall motion in Sr$_{2}$RuO$_{4}$

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 نشر من قبل Kohta Saitoh
 تاريخ النشر 2015
  مجال البحث فيزياء
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Clarifying the chiral domains structure of superconducting Sr$_{2}$RuO$_{4}$ has been a long-standing issue in identifying its peculiar topological superconducting state. We evaluated the critical current $I_{c}$ versus the magnetic field $H$ of Nb/Sr$_{2}$RuO$_{4}$ Josephson junctions, changing the junction dimension in expectation of that the number of domains in the junction is controlled. $I_{c}(H)$ exhibits a recovery from inversion symmetry breaking to invariance when the dimension is reduced to several microns. This inversion invariant behavior indicates the disappearance of domain walls; thus, the size of a single domain is estimated at approximately several microns.



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