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arXiv · 1706.06420

Dynamics and Control of Edge States in Laser-driven Graphene Nanoribbons

Matteo Puviani·Franca Manghi·Andrea Bertoni
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Abstract

An intense laser field in the high-frequency regime drives carriers in graphene nanoribbons (GNRs) out of equilibrium and creates topologically-protected edge states. Using Floquet theory on driven GNRs, we calculate the time evolution of local excitations of these edge states and show that they exhibit a robust dynamics also in the presence of very localized lattice defects (atomic vacancies), which is characteristic of topologically non-trivial behavior. We show how it is possible to control them by a modulated electrostatic potential: They can be fully transmitted on the same edge, reflected on the opposite one, or can be split between the two edges, in analogy with Hall edge states, making them promising candidates for flying-qubit architectures.

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Matteo Puviani, Franca Manghi, Andrea Bertoni. 2017-06-20. Dynamics and Control of Edge States in Laser-driven Graphene Nanoribbons. https://doi.org/10.1103/physrevb.95.235430

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