Electrical spin manipulation in graphene nanostructures
Abstract
We propose a mechanism to drive singlet-triplet spin transitions electrically, in a wide class of graphene nanostructures that present pairs of in-gap zero modes, localized at opposite sublattices. Examples are rectangular nanographenes with short zigzag edges, armchair ribbon heterojunctions with topological in-gap states and graphene islands with sp functionalization. The interplay between the hybridization of zero modes and Coulomb repulsion leads to symmetric exchange interaction that favors a singlet ground state. Application of an off-plane electric field to the graphene nanostructure generates an additional Rashba spin-orbit coupling, which results in antisymmetric exchange interaction that mixes and manifolds. We show that modulation in time of either the off-plane electric field or the applied magnetic field permits to perform electrically driven spin resonance in a system with very long spin relaxation times.
Cite
@article{arxiv.1712.07282,
title = {Electrical spin manipulation in graphene nanostructures},
author = {R. Ortiz and N. A. García-Martínez and J. L. Lado and J. Fernández-Rossier},
journal= {arXiv preprint arXiv:1712.07282},
year = {2018}
}