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arXiv · 1106.5768

Hexadecapolar Kondo effect in URu$_2$Si$_2$?

Anna I. Toth·Gabriel Kotliar
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Abstract

We derive the coupling of a localized hexadecapolar mode to conduction electrons in tetragonal symmetry. The derivation can be easily adapted to arbitrary multipoles in arbitrary environment. We relate our model to the two-channel Kondo (2CK) model and show that for an $f^2$-configuration, a relevant crystal field splitting in addition to the 2CK interaction is intrinsic to tetragonal symmetry. We discuss possible realizations of a hexadecapolar Kondo effect in URu$_2$Si$_2$. Solving our model we find good agreement with susceptibility and specific heat measurements in Th$_{1-x}$U$_x$Ru$_2$Si$_2$ ($x\ll1$).

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Anna I. Toth, Gabriel Kotliar. 2011-06-28. Hexadecapolar Kondo effect in URu$_2$Si$_2$?. https://doi.org/10.1103/physrevlett.107.266405

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