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arXiv · 1109.0275

Magnetic charge and ordering in kagome spin ice

Gia-Wei Chern·Oleg Tchernyshyov
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Abstract

We present a numerical study of magnetic ordering in spin ice on kagome, a two-dimensional lattice of corner-sharing triangles. The magnet has six ground states and the ordering occurs in two stages, as one might expect for a six-state clock model. In spin ice with short-range interactions up to second neighbors, there is an intermediate critical phase separated from the paramagnetic and ordered phases by Kosterlitz-Thouless transitions. In dipolar spin ice, the intermediate phase has long-range order of staggered magnetic charges. The high and low-temperature phase transitions are of the Ising and 3-state Potts universality classes, respectively. Freeze-out of defects in the charge order produces a very large spin correlation length in the intermediate phase. As a result of that, the lower-temperature transition appears to be of the Kosterlitz-Thouless type.

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Gia-Wei Chern, Oleg Tchernyshyov. 2012-04-11. Magnetic charge and ordering in kagome spin ice. https://doi.org/10.1098/rsta.2011.0388

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