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arXiv · 0805.3347

Halperin-Saslow modes as the origin of the low temperature anomaly in $NiGa_2S_4$

Daniel Podolsky·Yong Baek Kim
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Abstract

The absence of magnetic long range order in the triangular lattice spin-1 antiferromagnet $NiGa$_2$S$_4$ has prompted the search for a novel quantum ground state. In particular, several experiments suggest the presence of a linearly dispersing mode despite no long-range magnetic order. We show that the anomalous low temperature properties of NiGa$_2$S$_4$ can naturally be explained by the formulation developed by Halperin and Saslow where the linearly dispersing Halperin-Saslow mode may exist in the background of frozen spin moments and zero net magnetization. We provide highly non-trivial consistency checks on the existing experimental data and suggest future experiments that can further confirm the existence of the Halperin-Saslow mode. Our results place strong constraints on any microscopic theory of this material.

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Daniel Podolsky, Yong Baek Kim. 2008-05-21. Halperin-Saslow modes as the origin of the low temperature anomaly in $NiGa_2S_4$. https://doi.org/10.1103/physrevb.79.140402

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