Hybrid Plasmonic/Photonic Nanoscale Strategy for Multilevel Anticounterfeit Labels.

Area of Science:

• Materials Science
• Optics and Photonics
• Nanotechnology

Background:

• Increasing counterfeiting necessitates advanced goods authentication methods.
• Physical unclonable functions (PUFs) offer unique system characterization but classic PUFs face vulnerability due to widespread availability.
• Exploiting natural fabrication non-idealities is a common PUF implementation strategy.

Purpose of the Study:

• To propose a novel, three-level strong physical unclonable function (PUF) to combat counterfeiting.
• To leverage a hybrid plasmonic/photonic multilayered structure for enhanced security.
• To explore the potential of this PUF as an irreversible temperature exposure label.

Main Methods:

• Fabrication of a hybrid plasmonic/photonic multilayered structure with a resonant cavity and a top layer of plasmonic silver (Ag) nanoislands.
• Utilizing the random nanoscale morphology of Ag nanoislands as a manufacturer-resistant fingerprint.
• Tailoring the interplay between photonic and plasmonic modes to create chromatic and spectral security levels.

Main Results:

• The proposed structure functions as a three-level strong PUF, combining morphological, chromatic, and spectral security features.
• The unique chromatic signature and broad iridescence provide an additional security layer.
• The spectral response is accessible using common smartphone LEDs, demonstrating practical applicability.
• The architecture also serves as an irreversible quantitative temperature exposure label.

Conclusions:

• The developed hybrid plasmonic/photonic PUF offers a robust and multi-layered security solution against counterfeiting.
• The technology is scalable, cost-effective, and adaptable to various substrates, showing promise for morpho-cryptography applications.
• This innovative PUF design enhances goods authentication and provides a novel temperature sensing capability.