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arXiv · 0710.3737

Disorder, Metal-Insulator crossover and Phase diagram in high-Tc cuprates

F. Rullier-Albenque·H. Alloul·F. Balakirev·C. Proust
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Abstract

We have studied the influence of disorder induced by electron irradiation on the normal state resistivities $ρ(T)$ of optimally and underdoped YBa2CuOx single crystals, using pulsed magnetic fields up to 60T to completely restore the normal state. We evidence that point defect disorder induces low T upturns of rho(T) which saturate in some cases at low T in large applied fields as would be expected for a Kondo-like magnetic response. Moreover the magnitude of the upturns is related to the residual resistivity, that is to the concentration of defects and/or their nanoscale morphology. These upturns are found quantitatively identical to those reported in lower Tc cuprates, which establishes the importance of disorder in these supposedly pure compounds. We therefore propose a realistic phase diagram of the cuprates, including disorder, in which the superconducting state might reach the antiferromagnetic phase in the clean limit.

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F. Rullier-Albenque, H. Alloul, F. Balakirev, C. Proust. 2008-02-13. Disorder, Metal-Insulator crossover and Phase diagram in high-Tc cuprates. https://doi.org/10.1209/0295-5075/81/37008

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