Change of the Ground State upon Hole Doping Unveiled by Ni Impurity in High-$T_{\rm c}$ Cuprates

Yoichi Tanabe; Kensuke Suzuki; Tadashi Adachi; Yoji Koike; Takayuki Kawamata; Risdiana; Takao Suzuki; Isao Watanabe

doi:10.1143/jpsj.79.023706

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arXiv · 0911.1016

Change of the Ground State upon Hole Doping Unveiled by Ni Impurity in High-$T_{\rm c}$ Cuprates

Yoichi Tanabe·Kensuke Suzuki·Tadashi Adachi·Yoji Koike·Takayuki Kawamata·Risdiana·Takao Suzuki·Isao Watanabe

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Abstract

The electronic ground state in high-$T_{\rm c}$ cuprates where the superconducting state is suppressed by Ni substitution has been investigated in La$_{2-x}$Sr$_x$Cu$_{1-y}$Ni$_y$O$_4$ from the specific heat and muon spin relaxation measurements. It has been found that the ground state changes from a magnetically ordered state with the strong hole-trapping by Ni to a metallic state with the Kondo effect of Ni with increasing hole-concentration. Moreover, the analysis of the results has revealed that a phase separation into the magnetically ordered phase and the metallic phase occurs around the boundary of two phases.

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Yoichi Tanabe, Kensuke Suzuki, Tadashi Adachi, Yoji Koike, Takayuki Kawamata, Risdiana, Takao Suzuki, Isao Watanabe. 2010-02-11. Change of the Ground State upon Hole Doping Unveiled by Ni Impurity in High-$T_{\rm c}$ Cuprates. https://doi.org/10.1143/jpsj.79.023706

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