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Signatures of a momentum independent pseudogap in the electronic density of states and Raman spectroscopy of the underdoped cuprates

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 نشر من قبل James LeBlanc
 تاريخ النشر 2014
  مجال البحث فيزياء
والبحث باللغة English
 تأليف J.P.F. LeBlanc




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We propose a hybridization phenomenology to describe the pseudogap state of the underdoped cuprates. We show how a momentum independent pseudogap opens asymmetrically from the Fermi-surface but symmetric to the zeroes of the hybridized bonding dispersion, which results in false d-wave characteristics of the pseudogap at the Fermi level. By comparing against a d-wave form factor we illustrate the difficulty in identifying a momentum independent order in momentum averaged quantities such as the electronic Raman response. We identify a suppression in the single-particle density of states which produces a hump feature which should be observable experimentally in tunnelling $dI/dV$ spectra and distinguishes the s-wave and d-wave ordering scenarios.



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