Nonlinear manifestations of photon acceleration in time-dependent metasurfaces: tunable broadband harmonics generation
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 $\approx3.1\omega$. 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.
- Publication:
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arXiv e-prints
- Pub Date:
- October 2017
- DOI:
- 10.48550/arXiv.1710.06966
- arXiv:
- arXiv:1710.06966
- Bibcode:
- 2017arXiv171006966S
- Keywords:
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- Physics - Optics;
- Physics - Plasma Physics
- E-Print:
- Main: 10 pages, 4 figures