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arXiv · 1708.02776

Quantum criticality in a three dimensional spin system at zero field and pressure

K. Yu. Povarov·A. Mannig·G. Perren·J. S. Möller·E. Wulf·J. Ollivier·A. Zheludev
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Abstract

We report spontaneous appearance of antiferromagnetic order in a model gapped quantum paramagnet Ni(Cl$_{1-x}$Br$_x$)$_2$$\cdot$4SC(NH$_2$)$_2$ induced by a change in bromine concentration x. This transition is qualitatively similar to a z = 1 magnetic quantum critical point. However, the observed critical scaling of thermodynamic and magnetic properties has rather unusual critical exponents.

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K. Yu. Povarov, A. Mannig, G. Perren, J. S. Möller, E. Wulf, J. Ollivier, A. Zheludev. 2017-10-31. Quantum criticality in a three dimensional spin system at zero field and pressure. https://doi.org/10.1103/physrevb.96.140414

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