Photon acceleration and tunable broadband harmonics generation in nonlinear time-dependent metasurfaces

Area of Science:

• Nonlinear Optics
• Materials Science
• Quantum Electronics

Background:

• Photon acceleration, traditionally requiring high laser intensities, enhances photon energy and generates tunable harmonic pulses.
• Existing methods often necessitate extreme laser power and large propagation distances.

Purpose of the Study:

• To introduce a novel ultrathin semiconductor metasurface for efficient photon acceleration.
• To demonstrate photon acceleration at low laser intensities.
• To explore new pathways for nonlinear radiation sources.

Main Methods:

• Utilized ultrathin semiconductor metasurfaces as a novel nonlinear medium.
• Observed third-harmonic generation of near-infrared photons.
• Employed time-dependent coupled-mode theory for analysis and prediction.

Main Results:

• Achieved efficient photon acceleration at low laser intensities using semiconductor metasurfaces.
• Generated tunable third-harmonic photons with frequencies up to approximately 3.1ω.
• Experimental results showed good agreement with theoretical predictions.

Conclusions:

• Ultrathin semiconductor metasurfaces offer a new platform for efficient photon acceleration.
• This approach enables tunable nonlinear harmonic generation at significantly lower laser intensities.
• The findings predict a new route for nonlinear radiation sources combining resonant upconversion and broadband operation.