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arXiv · 1511.01972

Edge states and phase diagram for graphene under polarized light

Yi-Xiang Wang·Fuxiang Li
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Abstract

We investigate the topological phase transitions in graphene under the modulation of circularly polarized light, by analyzing the changes of edge states and its topological structures. A full phase diagram, with up to ten different topological phases, is presented in the parameter space spanned by the driving frequency and light strength. We find that the high-Chern number behavior is very common in the driven system. While the one-photon resonance can create the chiral edge states in the $π-$gap, the two-photon resonance will induce the counter-propagating edge modes in the zero-energy gap. When the driving light strength is strong, the number and even the chirality of the edge states may change in the $π-$gap. The robustness of the edge states to disorder potential are also examined. We close by discussing the feasibility of experimental proposals.

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Yi-Xiang Wang, Fuxiang Li. 2016-04-12. Edge states and phase diagram for graphene under polarized light. https://doi.org/10.1016/j.physb.2016.03.029

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