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Chiral Symmetry Breaking and Phase Fluctuations in Cuprate Superconductors: A QED$_3$ Unified Theory of the Pseudogap State

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 نشر من قبل Oskar Vafek
 تاريخ النشر 2001
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Z. Tesanovic




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A d-wave superconductor, its phase coherence progressively destroyed by unbinding of vortex-antivortex pairs, suffers an instability related to chiral symmetry breaking in two-flavor QED$_3$. The chiral manifold exhibits large degeneracy spanned by physical states acting as inherent ``competitors of d-wave superconductivity. Two of these states are associated with antiferromagnetic insulator and ``stripe phases, known to be stable in the pseudogap regime of cuprates near half-filling. The theory also predicts additional, yet unobserved state: a d+ip phase-incoherent superconductor.



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