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Hidden Order in $URu_2Si_2$

N. Shah·P. Chandra·P. Coleman·J. A. Mydosh
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Abstract

We review current attempts to characterize the underlying nature of the hidden order in $URu_2Si_2$. A wide variety of experiments point to the existence of two order parameters: a large primary order parameter of unknown character which co-exists with secondary antiferromagnetic order. Current theories can be divided into two groups determined by whether or not the primary order parameter breaks time-reversal symmetry. We propose a series of experiments designed to test the time-reversal nature of the underlying primary order in $URu_2Si_2$ and to characterize its local single-ion physics.

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N. Shah, P. Chandra, P. Coleman, J. A. Mydosh. 1999-04-18. Hidden Order in $URu_2Si_2$. https://doi.org/10.1103/physrevb.61.564

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