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arXiv · 1201.2181

Frustrated quantum critical theory of putative spin-liquid phenomenology in 6H-B-Ba3NiSb2O9

Gang Chen·Michael Hermele·Leo Radzihovsky
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Abstract

A recently discovered material, 6H-B-Ba3NiSb2O9 was found to display unusual low-temperature phenomenology, interpreted as a quantum spin liquid with spin S = 1 on a triangular lattice. We study a spin S = 1 quantum exchange model on an AB stacked triangular lattice near its quantum paramagnet-to-spiral magnet transition, driven by easy-plane single-ion anisotropy. We demonstrate that the frustrated inter- and intra-layer exchange interactions induce contour lines of low energy excitations that lead to a broad crossover regime of linear-temperature dependence of the specific heat. Based on this and a variety of other predictions, we argue that the observed phenomenology can be understood in terms of a conventional picture of a proximity to this frustrated critical point.

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Gang Chen, Michael Hermele, Leo Radzihovsky. 2012-01-10. Frustrated quantum critical theory of putative spin-liquid phenomenology in 6H-B-Ba3NiSb2O9. https://doi.org/10.1103/physrevlett.109.016402

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