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arXiv · 2006.06723

Double single-channel Kondo coupling in graphene with Fe molecules

Ignacio M. Vicent·Luca Chirolli·Francisco Guinea
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Abstract

We study the interaction between graphene and a single-molecule-magnet, [Fe4(L)2(dpm)6]. Focusing on the closest Iron ion in a hollow position with respect to the graphene sheet, we derive a channel selective tunneling Hamiltonian, that couples different d orbitals of the Iron atom to precise independent combinations of sublattice and valley degrees of freedom of the electrons in graphene. When looking at the spin-spin interaction between the molecule and the graphene electrons, close to the Dirac point the channel selectivity results in a channel decoupling of the Kondo interaction, with two almost independent Kondo systems weakly interacting among themselves. The formation of magnetic moments and the development of a full Kondo effect depends on the charge state of the graphene layer.

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Ignacio M. Vicent, Luca Chirolli, Francisco Guinea. 2020-06-11. Double single-channel Kondo coupling in graphene with Fe molecules. https://doi.org/10.1088/2399-6528%2Fac1303

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