Reentrant Kondo effect in Landau quantized graphene

Balázs Dóra; Peter Thalmeier

doi:10.1103/physrevb.76.115435

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arXiv · 0705.1934

Reentrant Kondo effect in Landau quantized graphene

Balázs Dóra·Peter Thalmeier

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Abstract

We have studied the interplay of an Anderson impurity in Landau quantized graphene, with special emphasis on the influence of the chemical potential. Within the slave-boson mean-field theory, we found reentrant Kondo behaviour by varying the chemical potential or gate voltage. Between Landau levels, the density of states is suppressed, and by changing the graphene's Fermi energy, we cross from metallic to semiconducting regions. Hence, the corresponding Kondo behaviour is also influenced. The f-level spectral function reveals both the presence of Landau levels in the conduction band and the Kondo resonance.

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Balázs Dóra, Peter Thalmeier. 2007-05-14. Reentrant Kondo effect in Landau quantized graphene. https://doi.org/10.1103/physrevb.76.115435

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