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arXiv · 1603.06027

First-principles study of the terahertz third-order nonlinear response of metallic armchair graphene nanoribbons

Yichao Wang·David R. Andersen
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Abstract

We compute the terahertz third-order nonlinear conductance of metallic armchair graphene nanoribbons using time-dependent perturbation theory. Significant enhancement of the intrinsic third-order conductance over the result for instrinsic 2D single-layer graphene is observed over a wide range of temperatures. We also investigate the nonlinear response of extrinsic metallic acGNR with |E_F|<<200 meV. We find that the third-order conductance exhibits a strong Fermi level dependence at low temperatures. A third-order critical field strength of between 1 and 5 kV/m is computed for the Kerr conductance as a function of temperature. For the third-harmonic conductance, the minimum critical field is computed to be about about 5 kV/m.

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Yichao Wang, David R. Andersen. 2016-05-31. First-principles study of the terahertz third-order nonlinear response of metallic armchair graphene nanoribbons. https://doi.org/10.1103/physrevb.93.235430

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