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Effects of doping on thermally excited quasiparticles in the high-$T_c$ superconducting state

T. Xiang·C. Panagopoulos
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Abstract

The physical properties of low energy superconducting quasiparticles in high- $T_c$ superconductors are examined using magnetic penetration depth and specific heat experimental data. We find that the low energy density of states of quasiparticles of La$_{2-x}$Sr$_x$CuO$_4$ scales with $(x-x_c)/T_c$ to the leading order approximation, where $x_c $ is the critical doping concentration below which $T_c=0$. The linear temperature term of the superfluid density is renormalized by quasiparticle interactions and the renormalization factor times the Fermi velocity is found to be doping independent.

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T. Xiang, C. Panagopoulos. 1999-12-14. Effects of doping on thermally excited quasiparticles in the high-$T_c$ superconducting state. https://doi.org/10.1103/physrevb.61.6343

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