Color Generation and Polarization-Sensitive Encryption by Laser Writing on Plasmonic Reflector Arrays

Area of Science:

• Materials Science
• Nanotechnology
• Optics

Background:

• Plasmonic color printing offers sustainable, durable color reproduction using nanostructures.
• Fabrication challenges have limited the widespread adoption of plasmonic nanostructures.

Purpose of the Study:

• To introduce plasmonic reflector arrays (PRAs) for advanced color printing and secure data encoding.
• To explore laser-based methods for fabricating and patterning PRAs.

Main Methods:

• Fabrication of three-layer PRAs (Ag NPs, Al2O3 spacer, Ag reflector) using physical vapor deposition (PVD).
• Manipulation of silver nanoparticle surface morphology via nanosecond and femtosecond laser writing.
• Development of a two-step laser method for embedding QR code patterns.

Main Results:

• Achieved diverse polarization-insensitive and polarization-sensitive structural colors.
• Demonstrated intricate pattern creation on PRAs using nanosecond laser writing.
• Successfully embedded QR code patterns for secure data applications.

Conclusions:

• PRAs fabricated via PVD and laser writing are promising for advanced color printing.
• Laser-processed PRAs offer potential for secure optical data encryption and transmission.