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arXiv · 2005.01189

Electronic nematicity in URu2Si2 revisited

Liran Wang·Mingquan He·Frederic Hardy·Dai Aoki·Kristin Willa·Jacques Flouquet·Christoph Meingast
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Abstract

The nature of the hidden-order (HO) state in URu2Si2 remains one of the major unsolved issues in heavy-fermion physics. Recently, torque magnetometry, x-ray diffraction and elastoresistivity data have suggested that the HO phase transition at THO = 17.5 K is driven by electronic nematic effects. Here, we search for thermodynamic signatures of this purported structural instability using anisotropic thermal-expansion, Young\'s modulus, elastoresistivity and specific-heat measurements. In contrast to the published results, we find no evidence of a rotational symmetry-breaking in any of our data. Interestingly, our elastoresistivity measurements, which are in full agreement with published results, exhibit a Curie-Weiss divergence, which we however attribute to a volume and not to a symmetry-breaking effect. Finally, clear evidence for thermal fluctuations is observed in our heat-capacity data, from which we estimate the HO correlation length.

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Liran Wang, Mingquan He, Frederic Hardy, Dai Aoki, Kristin Willa, Jacques Flouquet, Christoph Meingast. 2020-05-03. Electronic nematicity in URu2Si2 revisited. https://doi.org/10.1103/physrevlett.124.257601

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