Zn-induced wipeout effect on Cu NQR spectra in La$_{2-x}$Sr$_x$Cu$_{1-y}$Zn$_y$O$_4$

H. Yamagata; H. Miyamoto; K. Nakamura; M. Matsumura; Y. Itoh

doi:10.1016/s0921-4534(02)02419-x

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Zn-induced wipeout effect on Cu NQR spectra in La$_{2-x}$Sr$_x$Cu$_{1-y}$Zn$_y$O$_4$

H. Yamagata·H. Miyamoto·K. Nakamura·M. Matsumura·Y. Itoh

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Abstract

We report a systematic study of Zn-substitution effect on Cu NQR spectrum for high $T_c$ superconductors La$_{2-x}$Sr$_x$Cu$_{1-y}$Zn$_y$O$_4$ from carrier-underdoped to -overdoped regimes (polycrystalline samples, $x$ =0.10, 0.15, and 0.20). We observed no appreciable wipeout effect for the overdoped samples, a gradual and partial wipeout effect below about 80 K for the optimally doped ones, and very abrupt and full wipeout effect below about 40 K for the underdoped ones. The wipeout effect indicates a highly enhanced spectral weight of Cu spin fluctuations at a low frequency. We associate the wipeout effect with a Zn-induced local magnetism far above 40 K and with a localization effect below 40 K.

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H. Yamagata, H. Miyamoto, K. Nakamura, M. Matsumura, Y. Itoh. 2002-10-11. Zn-induced wipeout effect on Cu NQR spectra in La$_{2-x}$Sr$_x$Cu$_{1-y}$Zn$_y$O$_4$. https://doi.org/10.1016/s0921-4534(02)02419-x

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