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Critical doping in overdoped high-Tc superconductors - a Quantum Critical Point?

J. L. Tallon·J. W. Loram·G. V. M. Williams·J. R. Cooper·I. R. Fisher·J. D. Johnson·M. P. Staines·C. Bernhard
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Abstract

Evidence is presented from the scaling of the Knight shift, entropy and transport properties together with the sharp peaking of condensation energy, critical currents, superfluid density and a variety of other physical properties for the occurrence of a common critical doping point in lightly overdoped high-Tc superconductors (HTS). This critical doping lies at the point where the doping-dependent normal-state pseudogap energy, Eg, falls to zero and bears a strong, though incomplete, resemblance to a quantum critical point (QCP). A QCP scenario could lead directly to an explanation of the non-Fermi liquid behaviour of the normal-state metallic phase and the overall generic behaviour of the HTSC.

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J. L. Tallon, J. W. Loram, G. V. M. Williams, J. R. Cooper, I. R. Fisher, J. D. Johnson, M. P. Staines, C. Bernhard. 1999-11-11. Critical doping in overdoped high-Tc superconductors - a Quantum Critical Point?. https://doi.org/10.1002/(sici)1521-3951(199909)215%3A1%3C531%3A%3Aaid-pssb531%3E3.3.co%3B2-n

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