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Generation and Coherent Control of Pulsed Quantum Frequency Combs
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Continuous control of the nonlinearity phase for harmonic generations.

Guixin Li1, Shumei Chen1, Nitipat Pholchai2

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Summary

Researchers developed nonlinear metasurfaces enabling continuous phase control over local optical nonlinearity. This breakthrough allows for seamless generation and manipulation of harmonic waves in compact nanophotonic devices.

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Area of Science:

  • Nonlinear optics
  • Metasurfaces
  • Nanophotonics

Background:

  • Locally engineering nonlinear optical properties is essential in nonlinear optics.
  • Current methods like poling offer only binary control over nonlinearity, limiting phase manipulation.
  • A need exists for continuous control over nonlinear optical properties for advanced applications.

Purpose of the Study:

  • To experimentally demonstrate nonlinear metasurfaces with continuously controllable nonlinear polarizability.
  • To achieve spatially varying effective nonlinear polarizability with tunable phase.
  • To enable seamless generation and manipulation of harmonic waves.

Main Methods:

  • Utilizing nonlinear metasurfaces composed of nanoantennas with C3 and C4 rotational symmetries.
  • Implementing a concept inspired by spin-rotation coupling for phase control.
  • Demonstrating continuous phase control for second and third harmonic generation.

Main Results:

  • Achieved homogeneous linear optical properties with spatially varying nonlinear polarizability.
  • Demonstrated continuous phase control over local nonlinearity for harmonic generation.
  • Showcased complete control over the propagation of harmonic generation signals.

Conclusions:

  • The developed nonlinear metasurfaces offer continuous phase engineering of effective nonlinear polarizability.
  • This method integrates harmonic wave generation and manipulation.
  • Paves the way for developing highly compact and advanced nonlinear nanophotonic devices.