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arXiv · 1611.09777

Phase diagram of diluted Ising ferromagnet LiHo$_x$Y$_{1-x}$F$_4$

P. Babkevich·N. Nikseresht·I. Kovacevic·J. O. Piatek·B. Dalla Piazza·C. Kraemer·K. W. Krämer·K. Prokeš·S. Mat'aš·J. Jensen·H. M. Rønnow
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Abstract

We present a systematic study of the phase diagram of LiHo$_x$Y$_{1-x}$F$_4$ ($0.25<x<1$) Ising ferromagnets obtained from neutron scattering measurements and mean-field calculations. We show that while the thermal phase transition decreases linearly with dilution, as predicted by mean-field theory, the critical transverse field at the quantum critical point is suppressed much faster. This behavior is related to competition between off-diagonal dipolar coupling and quantum fluctuations that are tuned by doping and applied field, respectively. In this paper, we quantify the deviation of the experimental results from mean-field predictions, with the aim that this analysis can be used in future theoretical efforts towards a quantitative description.

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P. Babkevich, N. Nikseresht, I. Kovacevic, J. O. Piatek, B. Dalla Piazza, C. Kraemer, K. W. Krämer, K. Prokeš, S. Mat'aš, J. Jensen, H. M. Rønnow. 2016-11-29. Phase diagram of diluted Ising ferromagnet LiHo$_x$Y$_{1-x}$F$_4$. https://doi.org/10.1103/physrevb.94.174443

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