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Small Energy Scale for Mixed-Valent Uranium Materials

Mikito Koga·Daniel L. Cox
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Abstract

We investigate a two-channel Anderson impurity model with a $5f^1$ magnetic and a $5f^2$ quadrupolar ground doublet, and a $5f^2$ excited triplet. Using the numerical renormalization group method, we find a crossover to a non-Fermi liquid state below a temperature $T^*$ varying as the $5f^2$ triplet-doublet splitting to the 7/2 power. To within numerical accuracy, the non-linear magnetic susceptibility and the $5f^1$ contribution to the linear susceptibility are given by universal one-parameter scaling functions. These results may explain UBe$_{13}$ as mixed valent with a small crossover scale $T^*$.

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Mikito Koga, Daniel L. Cox. 1999-02-11. Small Energy Scale for Mixed-Valent Uranium Materials. https://doi.org/10.1103/physrevlett.82.2575

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