Nonlinear Terahertz Resonances from Ballistic Electron Funnelling
Abstract
We introduce a new mechanism for second-harmonic generation through geometrically rectifying-funneling-ballistic electrons in THz optical resonators. Our resonant rectifiers inherently act as second-order harmonic generators, rectifying currents without the presence of a potential barrier. Particle-in-cell simulations reveal that femtosecond electron-surface scattering plays a critical role in this process. We differentiate electron funneling from nonlocal plasmonic drag and bulk Dirac anharmonicity, showing that funneling can reduce the required field intensity for second-harmonic generation by 3-4 orders of magnitude. We provide design guidelines for generating funneling-induced second-harmonic generation, including resonance mode matching and materials selection. This approach offers a practical pathway for low-field, geometrically tunable THz upconversion and rectification, operating from sub-10 THz to multiple tens of THz in graphene.
Cite
@article{arxiv.2411.09212,
title = {Nonlinear Terahertz Resonances from Ballistic Electron Funnelling},
author = {Hue T. B. Do and Gregory K. Ngirmang and Wu Lin and Michel Bosman},
journal= {arXiv preprint arXiv:2411.09212},
year = {2025}
}
Comments
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