Muon spin relaxation study of the spin correlation in the overdoped regime of electron-doped high-Tc cuprate superconductors

M. A. Baqiya; T. Adachi; A. Takahashi; T. Konno; T. Ohgi; I. Watanabe; Y. Koike

doi:10.1103/physrevb.100.064514

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arXiv · 1908.01159

Muon spin relaxation study of the spin correlation in the overdoped regime of electron-doped high-Tc cuprate superconductors

M. A. Baqiya·T. Adachi·A. Takahashi·T. Konno·T. Ohgi·I. Watanabe·Y. Koike

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Abstract

In order to investigate the low-energy antiferromagnetic Cu-spin correlation and its relation to the superconductivity, we have performed muon spin relaxation (muSR) measurements using single crystals of the electron-doped high-Tc cuprate Pr_1-x_LaCe_x_CuO_4_ in the overdoped regime. The muSR spectra have revealed that the Cu-spin correlation is developed in the overdoped samples where the superconductivity appears. The development of the Cu-spin correlation weakens with increasing x and is negligibly small in the heavily overdoped sample where the superconductivity almost disappears. Considering that the Cu-spin correlation also exist in the superconducting electron-doped cuprates in the undoped and underdoped regimes [T. Adachi et al., J. Phys. Soc. Jpn. 85, 114716 (2016)], our findings suggest that the mechanism of the superconductivity is related to the low-energy Cu-spin correlation in the entire doping regime of the electron-doped cuprates.

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M. A. Baqiya, T. Adachi, A. Takahashi, T. Konno, T. Ohgi, I. Watanabe, Y. Koike. 2019-08-03. Muon spin relaxation study of the spin correlation in the overdoped regime of electron-doped high-Tc cuprate superconductors. https://doi.org/10.1103/physrevb.100.064514

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