The multiple symmetry sustaining phase transitions of spin ice

V. Raban , C. T. Suen , Ludovic Berthier (1) , P. C. W. Holdsworth

1 L2C - Laboratoire Charles Coulomb

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.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

V. Raban, C. T. Suen, Ludovic Berthier, P. C. W. Holdsworth. The multiple symmetry sustaining phase transitions of spin ice. Physical Review B, 2019, 99, pp.224425. ⟨10.1103/PhysRevB.99.224425⟩. ⟨hal-02200519⟩