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arXiv · 0810.0880

Genuine Phase Diagram of Homogeneously Doped CuO2 Plane in High-Tc Cuprate Superconductors

H. Mukuda·Y. Yamaguchi·S. Shimizu·Y. Kitaoka·P. M. Shirage·A. Iyo
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Abstract

We report a genuine phase diagram for a disorder-free CuO_2 plane based on the precise evaluation of the local hole density (N_h) by site-selective Cu-NMR studies on five-layered high-Tc cuprates. It has been unraveled that (1) the antiferromagnetic metallic state (AFMM) is robust up to N_h=0.17, (2) the uniformly mixed phase of superconductivity (SC) and AFMM is realized at N_h< 0.17, (3) the tetracritical point for the AFMM/(AFMM+SC)/SC/PM(Paramagnetism) phases may be present at N_h=0.15 and T=75 K, (4) Tc is maximum close to a quantum critical point (QCP) at which the AFM order collapses, suggesting the intimate relationship between the high-Tc SC and the AFM order. The results presented here strongly suggest that the AFM interaction plays the vital role as the glue for the Cooper pairs, which will lead us to a genuine understanding of why the Tc of cuprate superconductors is so high.

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H. Mukuda, Y. Yamaguchi, S. Shimizu, Y. Kitaoka, P. M. Shirage, A. Iyo. 2008-10-06. Genuine Phase Diagram of Homogeneously Doped CuO2 Plane in High-Tc Cuprate Superconductors. https://doi.org/10.1143/jpsj.77.124706

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