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Evidence for a generic novel quantum transition in high-Tc cuprates

C. Panagopoulos·J. L. Tallon·B. D. Rainford·T. Xiang·J. R. Cooper·C. A. Scott
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Abstract

We study the low-energy spin fluctuations and superfluid density of a series of pure and Zn-substituted high-$T_c$ superconductors (HTS) using the muon spin relaxation and $ac$-susceptibility techniques. At a critical doping state, $p_c$, we find (i) simultaneous abrupt changes in the magnetic spectrum in the superconducting ground state and (ii) that the slowing down of spin fluctuations becomes singular at T=0. These results provide experimental evidence for a novel quantum transition that separates the superconducting phase diagram of HTS into two distinct ground states.

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C. Panagopoulos, J. L. Tallon, B. D. Rainford, T. Xiang, J. R. Cooper, C. A. Scott. 2002-04-04. Evidence for a generic novel quantum transition in high-Tc cuprates. https://doi.org/10.1103/physrevb.66.064501

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