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arXiv · 1903.02778

The multiple symmetry sustaining phase transitions of spin ice

V. Raban·C. T. Suen·L. Berthier·P. C. W. Holdsworth
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Abstract

We present the full phase diagram of the dumbbell model of spin ice as a function of temperature, chemical potential and staggered chemical potential which breaks the translational lattice symmetry in favour of charge crystal ordering. We observe a double winged structure with five possible phases, monopole fluid (spin ice), fragmented single monopole crystal phases and double monopole crystal, the zinc blend structure. Our model provides a skeleton for liquid-liquid phase transitions and for the winged structures observed for itinerant magnets under pressure and external field. We relate our results to recent experiments on Ho$_2$Ir$_2$O$_7$ and propose a wide ranging set of new experiments that exploit the phase diagram, including high pressure protocols, dynamical scaling of Kibble-Zurek form and universal violations of the fluctuation-dissipation theorem.

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V. Raban, C. T. Suen, L. Berthier, P. C. W. Holdsworth. 2019-03-07. The multiple symmetry sustaining phase transitions of spin ice. https://doi.org/10.1103/physrevb.99.224425

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