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Effects of carrier concentration on the superfluid density of high-T_c cuprates

C. Panagopoulos·B. D. Rainford·J. R. Cooper·W. Lo·J. L. Tallon·J. W. Loram·J. Betouras·Y. S. Wang·C. W. Chu
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Abstract

The absolute values and temperature, T, dependence of the in-plane magnetic penetration depth, $λ_{ab}$, of La_{2-x}Sr_xCuO_4 and HgBa_2CuO_{4+δ} have been measured as a function of carrier concentration. We find that the superfluid density, $ρ_s$, changes substantially and systematically with doping. The values of $ρ_{s}(0)$ are closely linked to the available low energy spectral weight as determined by the electronic entropy just above T_c and the initial slope of $ρ_{s}(T)/ρ_{s}(0)$ increases rapidly with carrier concentration. The results are discussed in the context of a possible relationship between $ρ_s$ and the normal-state (or pseudo) energy gap.

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C. Panagopoulos, B. D. Rainford, J. R. Cooper, W. Lo, J. L. Tallon, J. W. Loram, J. Betouras, Y. S. Wang, C. W. Chu. 1999-03-06. Effects of carrier concentration on the superfluid density of high-T_c cuprates. https://doi.org/10.1103/physrevb.60.14617

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