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arXiv · 2005.10278

Kondo breakdown in a spin-1/2 chain of adatoms on a Dirac semimetal

Bimla Danu·Matthias Vojta·Fakher F. Assaad·Tarun Grover
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Abstract

We consider a spin-1/2 Heisenberg chain coupled via a Kondo interaction to two-dimensional Dirac fermions. The Kondo interaction is irrelevant at the \textit{decoupled} fixed-point, leading to the existence of a Kondo-breakdown phase and a Kondo-breakdown critical point separating such a phase from a heavy Fermi liquid. We reach this conclusion on the basis of a renormalization group analysis, large-N calculations as well as extensive auxiliary-field quantum Monte Carlo simulations. We extract quantities such as the zero-bias tunneling conductance which will be relevant to future experiments involving adatoms on semimetals such as graphene.

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Bimla Danu, Matthias Vojta, Fakher F. Assaad, Tarun Grover. 2020-05-20. Kondo breakdown in a spin-1/2 chain of adatoms on a Dirac semimetal. https://doi.org/10.1103/physrevlett.125.206602

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