Screening in anisotropic superfluids and the superfluid density in underdoped cuprates

Matthew J. Case; Igor F. Herbut

doi:10.1103/physrevb.72.104503

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Screening in anisotropic superfluids and the superfluid density in underdoped cuprates

Matthew J. Case·Igor F. Herbut

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Abstract

We examine the nature of the collective excitations in a strongly anisotropic system of bosons interacting via Coulomb interaction. Such a system has often been used in the past to model the effects of quantum and classical phase fluctuations on the superfluid density of underdoped cuprates. Depending on the anisotropy and the effective strength of the interaction we find four different regimes for the temperature dependence of the superfluid density. Coulomb interaction in underdoped cuprates is argued to be effectively short-ranged, and of order of unity in appropriately defined units.

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Matthew J. Case, Igor F. Herbut. 2005-07-06. Screening in anisotropic superfluids and the superfluid density in underdoped cuprates. https://doi.org/10.1103/physrevb.72.104503

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