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arXiv · 1704.06231

A Model for Metastable Magnetism in the Hidden-Order Phase of URu2Si2

Lance Boyer·Victor M. Yakovenko
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Abstract

We propose an explanation for the experiment by Schemm et al., Phys. Rev. B 91, 140506 (2015) where the polar Kerr effect (PKE), indicating time-reversal symmetry (TRS) breaking, was observed in the hidden-order (HO) phase of URu2Si2. The PKE signal on warmup was seen only if a training magnetic field was present on cool-down. Using a Ginzburg-Landau model for a complex order parameter, we show that the system can have a metastable ferromagnetic state producing the PKE, even if the HO ground state respects TRS. We predict that a strong reversed magnetic field should reset the PKE to zero.

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Lance Boyer, Victor M. Yakovenko. 2017-04-20. A Model for Metastable Magnetism in the Hidden-Order Phase of URu2Si2. https://doi.org/10.1016/j.aop.2017.11.024

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