One-and-a-half-channel Kondo model and its family of non-Fermi liquids

Anna I. Toth

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arXiv · 1708.08019

One-and-a-half-channel Kondo model and its family of non-Fermi liquids

Anna I. Toth

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Abstract

I construct non-Fermi liquid (NFL) quantum impurity models that are similar to the overscreened multi-channel Kondo models with the difference that an odd number of electron species screen the impurity. The simplest of them, named sesqui-channel (i.e. one-and-a-half-channel) Kondo (1.5CK) model, has less degrees of freedom and is simpler than the two-channel Kondo model, and yet it exhibits NFL physics. Using representation theory I derive the 1.5CK model for a spin-half impurity surrounded with electrons in cubic crystal field and solve it with the numerical renormalization group.

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Anna I. Toth. 2017-08-26. One-and-a-half-channel Kondo model and its family of non-Fermi liquids. https://arxiv.org/abs/1708.08019

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