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arXiv · 0910.5486

Study of the ground state properties of $LiHo_xY_{1-x}F_4$ using $μ$SR

J. Rodriguez·A. A. Aczel·J. P. Carlo·S. R. Dunsiger·G. J. MacDougall·P. L. Russo·A. T. Savici·Y. J. Uemura·C. R. Wiebe·G. M. Luke
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Abstract

$LiHo_xY_{1-x}F_4$ is an insulating system where the magnetic Ho$^{3+}$ ions have an Ising character, and interact mainly through magnetic dipolar fields. We used the muon spin relaxation technique to study the nature of the ground state for samples with x=0.25, 0.12, 0.08, 0.045 and 0.018. In contrast with some previous works, we have not found any signature of canonical spin glass behavior down to $\approx$15mK. Instead, below $\approx$300mK we observed dynamic magnetism characterized by a single correlation time with a temperature independent fluctuation rate. We observed that this low temperature fluctuation rate increases with x up to 0.08, above which it levels off. The 300mK energy scale corresponds to the Ho3+ hyperfine interaction strength, suggesting that the hyperfine interaction may be intimately involved with the spin dynamics in this system.

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J. Rodriguez, A. A. Aczel, J. P. Carlo, S. R. Dunsiger, G. J. MacDougall, P. L. Russo, A. T. Savici, Y. J. Uemura, C. R. Wiebe, G. M. Luke. 2009-10-28. Study of the ground state properties of $LiHo_xY_{1-x}F_4$ using $μ$SR. https://doi.org/10.1103/physrevlett.105.107203

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