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The superfluid density in cuprate high-Tc superconductors - a new paradigm

J. L. Tallon·J. W. Loram·J. R. Cooper·C. Panagopoulos·C. Bernhard
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Abstract

The doping dependence of the superfluid density, r_s, of high-Tc superconductors is usually considered in the context of the Uemura relation, namely Tc proportional to rs, which is generally assumed to apply in the underdoped regime. We show that a modified plot of Tc/Do versus rs, where Do is the maximum d-wave gap at T=0, exhibits universal features that point to an alternative interpretation of the underlying physics. In the underdoped region this plot exhibits the canonical negative curvature expected when a ground-state correlation competes with superconductivity (SC) by opening up a gap in the normal-state DOS. In particular rs is suppressed much faster than Tc/Do or indeed Tc. The pseudogap is found to strongly modify the SC ground state.

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J. L. Tallon, J. W. Loram, J. R. Cooper, C. Panagopoulos, C. Bernhard. 2002-11-05. The superfluid density in cuprate high-Tc superconductors - a new paradigm. https://doi.org/10.1103/physrevb.68.180501

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