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arXiv · 1612.02973

Raman Active High Energy Excitations in URu$_2$Si$_2$

Jonathan Buhot·Yann Gallais·Maximilien Cazayous·Alain Sacuto·Przemysław Piekarz·Gérard Lapertot·Dai Aoki·Marie-Aude Méasson
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Abstract

We have performed Raman scattering measurements on URu$_2$Si$_2$ single crystals on a large energy range up to $\sim$ 1300 cm$^{-1}$ and in all the Raman active symmetries as a function of temperature down to 15 K. A large excitation, active only in the E$_{g}$ symmetry, is reported. It has been assigned to a crystal electric field excitation on the Uranium site. We discuss how this constrains the crystal electric field scheme of the Uranium ions. Furthermore, three excitations in the A$_{1g}$ symmetry are observed. They have been associated to double Raman phonon processes consistently with ab initio calculations of the phonons dispersion.

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Jonathan Buhot, Yann Gallais, Maximilien Cazayous, Alain Sacuto, Przemysław Piekarz, Gérard Lapertot, Dai Aoki, Marie-Aude Méasson. 2016-12-09. Raman Active High Energy Excitations in URu$_2$Si$_2$. https://doi.org/10.1016/j.physb.2016.10.034

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