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arXiv · 1606.00676

Nonlinear response of metallic acGNR to an elliptically-polarized terahertz excitation field

Yichao Wang·David R. Andersen
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Abstract

We present a theoretical description of the nonlinear response induced by an elliptically-polarized terahertz beam normally-incident on intrinsic and extrinsic metallic armchair graphene nanorib- bons. Our results show that using a straightforward experimental setup, it should be possible to observe novel polarization-dependent nonlinearities at low excitation field strengths of the or- der of 10 4 V/m. At low temperatures the Kerr nonlinearities in extrinsic nanoribbons persist to significantly higher excitation frequencies than they do for linear polarizations, and at room tem- peratures, the third-harmonic nonlinearities are enhanced by 2-3 orders of magnitude. Finally, the Fermi-level and temperature dependence of the nonlinear response is characterized.

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Yichao Wang, David R. Andersen. 2016-06-24. Nonlinear response of metallic acGNR to an elliptically-polarized terahertz excitation field. https://doi.org/10.1109/jstqe.2016.2641300

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