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arXiv · 1805.11307

Anisotropic Kondo pseudo-gap in URu2Si2

J. Buhot·X. Montiel·Y. Gallais·M. Cazayous·A. Sacuto·G. Lapertot·D. Aoki·N. E. Hussey·C. Pépin·S. Burdin·M. -A. Méasson
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Abstract

A polarized electronic Raman scattering study reveals the emergence of symmetry dependence in the electronic Raman response of single crystalline URu$_{2}$Si$_{2}$ below the Kondo crossover scale $T_K\sim100K$. In particular, the development of a coherent Kondo pseudo-gap predominantly in the E$_g$ channel highlights strong anisotropy in the Kondo physics in URu$_{2}$Si$_{2}$ that has previously been neglected in theoretical models of this system. A calculation of the Raman vertices demonstrates that the strongest Raman vertex does indeed develop within the E$_g$ channel for interband transitions and reaches a maximum along the diagonals of the Brillouin zone, implying a d-wave-like geometry for the Kondo pseudo-gap. Below the hidden order phase transition at $T_{HO}= 17.5K$, the magnitude of the pseudo-gap is found to be enhanced. Moreover, the anisotropy of the pseudo-gap is similar in form to that proposed for the chiral d-wave (E$_g$) superconducting state that appears below $T_c=1.5K$.

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J. Buhot, X. Montiel, Y. Gallais, M. Cazayous, A. Sacuto, G. Lapertot, D. Aoki, N. E. Hussey, C. Pépin, S. Burdin, M. -A. Méasson. 2018-07-13. Anisotropic Kondo pseudo-gap in URu2Si2. https://doi.org/10.1103/physrevb.101.245103

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