Nonlinear asymmetric imaging with AlGaAs metasurface

Area of Science:

• Photonics and Nanotechnology
• Nonlinear Optics
• Metasurface Technology

Background:

• Dielectric metasurfaces are versatile platforms for applications like sensing and nonlinear optics.
• Asymmetric metasurface geometries are gaining interest for enhanced light control.
• Nonlinear light-matter interactions in metasurfaces offer miniaturized optical control.

Purpose of the Study:

• To demonstrate nonlinear asymmetric light generation in a dielectric metasurface using second harmonic generation.
• To investigate the effect of illumination direction on nonlinear emitted power.
• To explore the potential for generating different images via reversed illumination.

Main Methods:

• Fabrication of a dielectric metasurface with asymmetric geometry.
• Utilizing second harmonic generation (SHG) as the nonlinear process.
• Modulating pump illumination direction to study nonlinear emission characteristics.

Main Results:

• Demonstrated significant modulation (over one order of magnitude) of nonlinear emitted power by inverting illumination direction.
• Showcased the ability of the designed metasurface to generate two distinct images at the second harmonic with reversed illumination.
• Confirmed nonlinear asymmetric light generation in the dielectric metasurface.

Conclusions:

• Asymmetric dielectric metasurfaces provide a route for tunable nonlinear light generation.
• The demonstrated directional control of nonlinear emission and imaging holds promise for advanced nanophotonic devices.
• This work opens opportunities for compact, integrated nanophotonic devices for imaging applications.