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Dynamic properties of a diluted pyrochlore cooperative paramagnet (Tb_pY_{1-p})_2Ti_2O_7

A. Keren·J. S. Gardner·G. Ehlers·A. Fukaya·E. Sagi·Y. J. Uemura
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Abstract

Investigations of the spin dynamics of the geometrically frustrated pyrochlore (Tb_pY_{1-p})_2Ti_2O_7, using muon spin relaxation and neutron spin echo, as a function of magnetic coverage p, have been carried out. Our major finding is that paramagnetic fluctuations prevail as T->0 for all values of p, and that they are sensitive to dilution, indicating a cooperative spin motion. However, the percolation threshold p_c is not a critical point for the fluctuations. We also find that the low temperatures spectral density has a 1/f behavior, and that dilution slows down the spin fluctuations.

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A. Keren, J. S. Gardner, G. Ehlers, A. Fukaya, E. Sagi, Y. J. Uemura. 2004-07-06. Dynamic properties of a diluted pyrochlore cooperative paramagnet (Tb_pY_{1-p})_2Ti_2O_7. https://doi.org/10.1103/physrevlett.92.107204

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