Nonlinear Optical Information Encoding with Grayscale Lithography Enabled Metasurfaces

Area of Science:

• Nanophotonics
• Metasurfaces
• Optical Information Encoding

Background:

• Optical information encoding is crucial for sensing, data storage, and computing.
• Optical metasurfaces offer flexible light manipulation but often require multiple meta-atoms per unit cell, limiting information density.
• Existing metasurface designs struggle to achieve simultaneous amplitude and phase control efficiently.

Purpose of the Study:

• To develop a novel approach for high-density optical information encoding.
• To achieve precise control over both amplitude and phase of light at the single-pixel level.
• To explore advanced nonlinear nanophotonic sources.

Main Methods:

• Fabrication of hybrid metasurfaces using gold plasmonic meta-atoms on an epsilon-near-zero material.
• Utilizing electron beam grayscale lithography to control spacer layer thickness.
• Varying the orientation angles of meta-atoms for light manipulation.

Main Results:

• Demonstrated single-pixel level control of both amplitude and phase of generated second-harmonic waves.
• Achieved high information density by overcoming limitations of traditional metasurfaces.
• Successfully encoded optical information using nonlinear effects.

Conclusions:

• The developed method enables advanced nonlinear optical information encoding.
• This approach opens new possibilities for creating sophisticated nonlinear nanophotonic devices.
• The hybrid metasurface design offers a promising platform for future optical technologies.