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arXiv · 1710.06966

Nonlinear manifestations of photon acceleration in time-dependent metasurfaces: tunable broadband harmonics generation

Maxim R. Shcherbakov·Kevin Werner·Zhiyuan Fan·Noah Talisa·Enam Chowdhury·Gennady Shvets
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Abstract

Time-dependent nonlinear media, such as rapidly generated plasmas produced via laser ionization of gases, can increase the energy of individual laser photons and generate tunable high-order harmonic pulses. This phenomenon, known as photon acceleration, has traditionally required extreme-intensity laser pulses and macroscopic propagation lengths. Here, we report on a novel nonlinear material$-$an ultrathin semiconductor metasurface$-$that exhibits efficient photon acceleration at low intensities. We observe a signature nonlinear manifestation of photon acceleration: third-harmonic generation of near-infrared photons with tunable frequencies reaching up to $\approx3.1ω$. A simple time-dependent coupled-mode theory, found to be in good agreement with experimental results, is utilized to predict a new path towards nonlinear radiation sources that combine resonant upconversion with broadband operation.

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Maxim R. Shcherbakov, Kevin Werner, Zhiyuan Fan, Noah Talisa, Enam Chowdhury, Gennady Shvets. 2019-01-13. Nonlinear manifestations of photon acceleration in time-dependent metasurfaces: tunable broadband harmonics generation. https://arxiv.org/abs/1710.06966

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