Solvent-triggered reconfiguration of optical physical unclonable functions

Area of Science:

• Optoelectronics
• Materials Science
• Artificial Intelligence

Background:

• Optical physical unclonable functions (OPUFs) offer unique artificial fingerprints via light-matter interactions.
• Static OPUF architectures lack adaptive defense, limiting their practical application.
• Existing reconfigurable OPUFs using phase-change materials are prone to unintended environmental activation.

Purpose of the Study:

• To introduce a novel solvent-triggered reconfiguration strategy for optical physical unclonable functions.
• To address the trade-off between environmental stability and reconfigurability in OPUFs.
• To develop a robust authentication framework for dynamically changing OPUF configurations.

Main Methods:

• Utilized polymeric microcube arrays confined within microwells, allowing translational and rotational freedom.
• Employed a volatile solvent to induce swelling, wall-cube contact, and subsequent evaporation-driven detachment for non-deterministic rearrangement.
• Integrated a machine-learning-based authentication framework to identify unique spatial configurations.

Main Results:

• Demonstrated solvent-induced, non-deterministic rearrangement of microcubes to generate new spatial configurations and optical fingerprints.
• Achieved remarkable stability against environmental and mechanical stresses.
• Successfully decoupled environmental stability from reconfigurability using a solvent-triggered mechanism.

Conclusions:

• The proposed solvent-triggered OPUF system offers a robust and adaptive security solution.
• This approach overcomes the limitations of static and environmentally sensitive reconfigurable OPUFs.
• The combination of microfluidics, material rearrangement, and machine learning presents a promising direction for next-generation security devices.