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arXiv · 1104.3108

Electric-field controlled spin in bilayer triangular graphene quantum dots

A. D. Guclu·P. Potasz·P. Hawrylak
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Abstract

We present theoretical results based on mean-field and exact many-body approaches showing that in bilayer triangular graphene quantum dots with zigzag edges the magnetism can be controlled by an external vertical electric-field. We demonstrate that without electric field the spins of the two layers of the quantum dot interact ferromagnetically. At a critical value of the electric-field, the total spin of the bilayer structure can be turned off or reduced to a single localized spin, a qubit isolated from contacts and free from interaction with nuclear spins.

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A. D. Guclu, P. Potasz, P. Hawrylak. 2011-04-15. Electric-field controlled spin in bilayer triangular graphene quantum dots. https://doi.org/10.1103/physrevb.84.035425

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