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Magnetic Phase Diagram of the Hole-doped Ca$_{2-x}$Na$_{x}$CuO$_{2}$Cl$_{2}$ Cuprate Superconductor

K. Ohishi·I. Yamada·A. Koda·W. Higemoto·S. R. Saha·R. Kadono·K. M. Kojima·M. Azuma·M. Takano
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Abstract

We report on the magnetic phase diagram of a hole-doped cuprate Ca$_{2-x}$Na$_{x}$CuO$_{2}$Cl$_{2}$, which is free from buckling of CuO$_2$ planes, determined by muon spin rotation and relaxation. It is characterized by a quasi-static spin glass-like phase over a range of sodium concentration ($0.05\leq x\leq 0.12$), which is held between long range antiferromagnetic (AF) phase ($x\leq 0.02$) and superconducting phase where the system is non-magnetic for $x\geq 0.15$. The obtained phase diagram qualitatively agrees well with that commonly found for hole-doped high-\tc cuprates, strongly suggesting that the incomplete suppression of the AF order for $x>0.02$ is an essential feature of the hole-doped cuprates.

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K. Ohishi, I. Yamada, A. Koda, W. Higemoto, S. R. Saha, R. Kadono, K. M. Kojima, M. Azuma, M. Takano. 2004-12-13. Magnetic Phase Diagram of the Hole-doped Ca$_{2-x}$Na$_{x}$CuO$_{2}$Cl$_{2}$ Cuprate Superconductor. https://doi.org/10.1143/jpsj.74.2408

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