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Systematic (63)Cu NQR and (89)Y NMR Study of Spin Dynamics in Y(1-z)Ca(z)Ba(2)Cu(3)O(y) Across Superconductor-Insulator Boundary

P. M. Singer·T. Imai
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Abstract

We demonstrate that the spin dynamics in underdoped Y(1-z)Ca(z)Ba(2)Cu(3)O(y) for y=~6.0 exhibit qualitatively the same behavior to underdoped La(2-x)Sr(x)CuO(4) for an equal amount of hole concentration p=z/2=x<0.11. However,a spin-gap appears as more holes are doped into the CuO(2) plane by increasing the oxygen concentration to y=~6.5 for a fixed value of Ca concentration z. Our results also suggest that Ca doping causes disorder effects that enhance the low frequency spin fluctuations.

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P. M. Singer, T. Imai. 2002-04-05. Systematic (63)Cu NQR and (89)Y NMR Study of Spin Dynamics in Y(1-z)Ca(z)Ba(2)Cu(3)O(y) Across Superconductor-Insulator Boundary. https://arxiv.org/abs/cond-mat/0112234

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