López, Molina (2020) Photoprotected spin Hall effect on graphene with substrate induced Rashba spin-orbit coupling Journal of physics. Condensed matter : an Institute of Physics journal 32(20) 205701

Abstract

We propose an experimental realization of the spin Hall effect in graphene by illuminating a graphene sheet on top of a substrate with circularly polarized monochromatic light. The substrate induces a controllable Rashba type spin-orbit coupling which breaks the spin-degeneracy of the Dirac cones but it is gapless. The circularly polarized light induces a gap in the spectrum and turns graphene into a Floquet topological insulator with spin dependent edge states. By analyzing the high and intermediate frequency regimes, we find that in both parameter limits, the spin-Chern number can be tuned by the effective coupling strength of the charge particles to the radiation field and determine the condition for the photoinduced topological phase transition.

Links

http://www.ncbi.nlm.nih.gov/pubmed/31945749
http://dx.doi.org/10.1088/1361-648X/ab6cc0

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