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Updated: Jun 28, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Directionally tunable co- and counterpropagating photon pairs from a nonlinear metasurface
Maximilian A Weissflog1,2, Jinyong Ma3, Jihua Zhang3,4
1Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, 07745 Jena, Germany.
Nanophotonics (Berlin, Germany)
|December 5, 2024
Summary
Researchers precisely controlled photon pair emission angles from nonlinear metasurfaces. This breakthrough enables tunable, efficient generation of entangled photon pairs, advancing quantum optics and photon-pair sources.
Area of Science:
- Quantum Optics
- Nanophotonics
- Materials Science
Background:
- Nonlinear metasurfaces are emerging platforms for quantum light generation.
- Precise control over photon-pair properties, like emission angle, remains a challenge.
- Classical nonlinear optics in metasurfaces offers high light manipulation, but this is underdeveloped for photon pairs.
Purpose of the Study:
- To theoretically and experimentally demonstrate precise control over the emission angle of photon pairs generated from nonlinear metasurfaces.
- To establish a straightforward design strategy for tunable photon-pair generation in such devices.
- To advance the capabilities of subwavelength-thickness photon-pair sources.
Main Methods:
- Utilized nonlinear metasurfaces composed of a silicon dioxide grating on a lithium niobate guiding layer.
- Employed transverse phase matching of guided-mode resonances with strong angular dispersion.
- Performed theoretical calculations and experimental measurements of photon-pair generation.
- Achieved all-optical emission angle tuning via pump wavelength modulation.
Main Results:
- Demonstrated precise, angularly tunable photon-pair generation for the first time.
- Achieved high coincidence-to-accidental ratios for both co- and counterpropagating emission.
- Validated theoretical predictions with experimental results, showing good agreement.
- Presented a practical design strategy for nonlinear metasurface photon-pair sources.
Conclusions:
- Precise angular control of photon-pair emission from nonlinear metasurfaces is achievable.
- The developed method offers tunable, efficient generation of photon pairs.
- This work significantly enhances the toolkit for subwavelength-thickness quantum light sources.
- Future extensions may include electro-optic modulation for enhanced control.
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