J A M Paddison, H S Ong, J O Hamp, P Mukherjee, X Bai, M G Tucker, N P Butch, C Castelnovo, M Mourigal, and S E Dutton, Emergent Order in the Kagome Ising Magnet Dy3Mg2Sb3O14, Nature Communications 7, 13842 (2016)
Press: Georgia Tech

Emergent charge-disordered and emergent-charge ordered states of the kagome Ising magnet Dy3Mg2Sb3O14 (right), and the corresponding magnetic neutron-scattering data (left). Emergent charges are shown in red/blue and spin structures as black arrows.
The Ising model—in which degrees of freedom (spins) are binary valued (up/down)—is a cornerstone of statistical physics that shows rich behaviour when spins occupy a highly frustrated lattice such as kagome. Here we show that the layered Ising magnet Dy3Mg2Sb3O14 hosts an emergent order predicted theoretically for individual kagome layers of in-plane Ising spins. Neutron-scattering and bulk thermomagnetic measurements reveal a phase transition at ~0.3 K from a disordered spin-ice-like regime to an emergent charge ordered state, in which emergent magnetic charge degrees of freedom exhibit three-dimensional order while spins remain partially disordered. Monte Carlo simulations show that an interplay of inter-layer interactions, spin canting and chemical disorder stabilizes this state. Our results establish Dy3Mg2Sb3O14 as a tuneable system to study interacting emergent charges arising from kagome Ising frustration.