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Low-field octupoles and high-field quadrupoles in URu2Si2

Annamaria Kiss·Patrik Fazekas
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Abstract

The recent experimental finding of large-amplitude antiferromagnetism induced by uniaxial strain shows that the "hidden" low-field order of URu2Si2 breaks time reversal invariance. We propose a new crystal field model which supports T(beta)z octupolar order in the low-field phase, and quadrupolar order in a disjoint high-field phase. The temperature dependence of the linear and third order magnetic susceptibility is in good agreement with the observed behavior.

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Annamaria Kiss, Patrik Fazekas. 2004-04-05. Low-field octupoles and high-field quadrupoles in URu2Si2. https://arxiv.org/abs/cond-mat/0404099

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