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arXiv · 1305.0075

Kondo effect in monolayer and bilayer graphene: physical realizations of the multi-channel Kondo models

Maxim Kharitonov·Gabriel Kotliar
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Abstract

We perform a general group-theoretical study of the Kondo problem in monolayer and bilayer graphene around the charge neutrality point. Utilizing the group representation theory, we derive from symmetry considerations a family of the Kondo models for all symmetric placements with either 3- or 6-fold rotational axis of an impurity atom in an arbitrary orbital state. We find six possible classes of the partially anisotropic four-channel Kondo model. As the key result, we argue several possibilities to realize the regime of the dominant channel-symmetric two-channel Kondo effect, protected by the local symmetry and specifics of the graphene band structure. Our findings open prospects for the observation of the rich multi-channel Kondo physics in graphene and the associated non-Fermi-liquid behavior.

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Maxim Kharitonov, Gabriel Kotliar. 2013-05-01. Kondo effect in monolayer and bilayer graphene: physical realizations of the multi-channel Kondo models. https://doi.org/10.1103/physrevb.88.201103

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