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arXiv · 2204.11664

Harmonic generation in bent graphene with artificially-enhanced spin-orbit coupling

Arttu Nieminen·Marco Ornigotti
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Abstract

We theoretically investigate the nonlinear response of bent graphene, in the presence of artificially-enhanced spin-orbit coupling, which can occur either via adatom deposition, or by placing the sheet of bent graphene in contact with a spin-orbit active substrate. We discuss the interplay between the spin-orbit coupling and the artificial magnetic field generated by the bending, for both the cases of Rashba and intrinsic spin-orbit coupling. For the latter, we introduce a spin-field interaction Hamiltonian addressing directly the electron spin as a degree of freedom. Our findings reveal that in this case, by controlling the amount of spin-orbit coupling, it is possible to significantly tune the spectrum of the nonlinear signal, achieving, in principle, efficient conversion of light from THz to UV region.

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Arttu Nieminen, Marco Ornigotti. 2022-09-09. Harmonic generation in bent graphene with artificially-enhanced spin-orbit coupling. https://doi.org/10.1103/physreva.106.043517

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