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arXiv · 1611.07284

Fermi/non-Fermi mixing in SU($N$) Kondo effect

Taro Kimura·Sho Ozaki
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Abstract

We apply conformal field theory analysis to the $k$-channel SU($N$) Kondo system, and find a peculiar behavior in the cases $N > k > 1$, which we call Fermi/non-Fermi mixing: The low temperature scaling is described as the Fermi liquid, while the zero temperature IR fixed point exhibits the non-Fermi liquid signature. We also show that the Wilson ratio is no longer universal for the cases $N > k > 1$. The deviation from the universal value of the Wilson ratio could be used as an experimental signal of the Fermi/non-Fermi mixing.

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Taro Kimura, Sho Ozaki. 2016-11-22. Fermi/non-Fermi mixing in SU($N$) Kondo effect. https://doi.org/10.7566/jpsj.86.084703

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