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arXiv · 1207.2433

Basal-Plane Nonlinear Susceptibility: A Direct Probe of the Single-Ion Physics in URu2Si2

Rebecca Flint·Premala Chandra·Piers Coleman
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Abstract

The microscopic nature of the hidden order state in URu2Si2 is dependent on the low-energy configurations of the uranium ions, and there is currently no consensus on whether it is predominantly 5f^2 or 5f^3. Here we show that measurement of the basal-plane nonlinear susceptibility can resolve this issue; its sign at low-temperatures is a distinguishing factor. We calculate the linear and nonlinear susceptibilities for specific 5f^2 and 5f^3 crystal-field schemes that are consistent with current experiment. Because of its dual magnetic and orbital character, a \Gamma_5 magnetic non-Kramers doublet ground-state of the U ion can be identified by $\chi_1^c(T) \propto \chi_3^\perp(T)$ where we have determined the constant of proportionality for URu2Si2.

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Rebecca Flint, Premala Chandra, Piers Coleman. 2012-07-10. Basal-Plane Nonlinear Susceptibility: A Direct Probe of the Single-Ion Physics in URu2Si2. https://doi.org/10.1103/physrevb.86.155155

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