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arXiv · 1309.6457

Indirect coupling between localized magnetic moments in zero-dimensional graphene nanostructures (quantum dots)

Karol Szałowski
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Abstract

The indirect Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling between on-site magnetic impurities is studied for two kinds of graphene nanoflakes consisting of approximately 100 carbon atoms, posessing either zigzag or armchair edge. The tight-binding Hamiltonian with Hubbard term is used in non-perturbative calculations of coupling between the impurities placed at the edge of the structure. In general, for zigzag-edged nanoflakes a pronounced coupling robust against charge doping is found, while for armchair-edged structures the interaction is weaker and much more sensitive to charge doping. Also the distance dependence of indirect exchange differs significantly for both edge forms.

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Karol Szałowski. 2013-10-24. Indirect coupling between localized magnetic moments in zero-dimensional graphene nanostructures (quantum dots). https://doi.org/10.12693/aphyspola.126.236

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