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arXiv · 1506.03796

Spectroscopic determination of the atomic f-electron symmetry underlying hidden order in URu$_2$Si$_2$

L. Andrew Wray·Jonathan Denlinger·Shih-Wen Huang·Haowei He·Nicholas P. Butch·M. Brian Maple·Zahid Hussain·Yi-De Chuang
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Abstract

The low temperature hidden order state of URu$_2$Si$_2$ has long been a subject of intense speculation, and is thought to represent an as yet undetermined many-body quantum state not realized by other known materials. Here, X-ray absorption spectroscopy (XAS) and high resolution resonant inelastic X-ray scattering (RIXS) are used to observe electronic excitation spectra of URu$_2$Si$_2$, as a means to identify the degrees of freedom available to constitute the hidden order wavefunction. Excitations are shown to have symmetries that derive from a correlated $5f^2$ atomic multiplet basis that is modified by itinerancy. The features, amplitude and temperature dependence of linear dichroism are in agreement with ground states that closely resemble the doublet $\Gamma_5$ crystal field state of uranium.

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L. Andrew Wray, Jonathan Denlinger, Shih-Wen Huang, Haowei He, Nicholas P. Butch, M. Brian Maple, Zahid Hussain, Yi-De Chuang. 2015-06-11. Spectroscopic determination of the atomic f-electron symmetry underlying hidden order in URu$_2$Si$_2$. https://doi.org/10.1103/physrevlett.114.236401

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