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arXiv · 1512.08095

Strong electron correlation behind the superconductivity in Ce-free and Ce-underdoped high-Tc T'-cuprates

T. Adachi·A. Takahashi·K. M. Suzuki·M. A. Baqiya·T. Konno·T. Takamatsu·M. Kato·I. Watanabe·A. Koda·M. Miyazaki·R. Kadono·Y. Koike
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Abstract

In order to investigate the electronic state of Ce-free and Ce-underdoped high-Tc cuprates with the so-called T' structure, we have performed muon-spin-relaxation (muSR) and specific-heat measurements of Ce-free T'-La_1.8_Eu_0.2_CuO_4+d_ (T'-LECO) polycrystals and Ce-underdoped T'-Pr_1.3-x_La_0.7_Ce_x_CuO_4+d_ (T'-PLCCO) single crystals with x=0.10. The muSR spectra of the reduced superconducting samples of both T'-LECO with Tc=15K and T'-PLCCO with x=0.10 and Tc=27K have revealed that a short-range magnetic order coexists with the superconductivity in the ground state. The formation of a short-range magnetic order due to a tiny amount of excess oxygen in the reduced superconducting samples strongly suggest that the Ce-free and Ce-underdoped T'-cuprates are regarded as strongly correlated electron systems.

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T. Adachi, A. Takahashi, K. M. Suzuki, M. A. Baqiya, T. Konno, T. Takamatsu, M. Kato, I. Watanabe, A. Koda, M. Miyazaki, R. Kadono, Y. Koike. 2015-12-26. Strong electron correlation behind the superconductivity in Ce-free and Ce-underdoped high-Tc T'-cuprates. https://doi.org/10.7566/jpsj.85.114716

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