A High-Security mutual authentication system based on structural color-based physical unclonable functions labels

Abstract

Optical physical unclonable functions (PUFs) have been considered to be one of the powerful tools to curb counterfeiting due to the unpredictable preparation process and identifiable information content. Responsive colloidal photonic crystals capable of controlling and manipulating light propagation exhibit low optical loss, stability and hiding function, which are more suitable to accomplish the safety and practicability of optical PUF labels. Herein, structural color-based PUF labels (SCPLs) prepared by injection-casting colloidal crystals propose a highly efficient and stable PUF authentication. With the decimal encode of the reflection intensity level at each pixel, the SCPL can achieve a theoretical encoding capacity of 102500 at 50 × 50 pixels. Utilizing the responsiveness of SCPLs, the PUF features can be switched between invisible and visible states to hide PUF information. Moreover, authentication experiments confirmed that the robustness of SCPL reached 0.994 and 0.960 in tensile test and wetting–drying cycle test, respectively, indicating that SCPL with hiding function, low optical loss and stability can be authenticated multiple times in practical applications. Interestingly, a high-security mutual authentication system for supply chain based on digital storage secret keys is proposed to showcase the strong application potential of SCPLs for various fields such as confidentiality of materials/technologies, dynamic anti-counterfeiting/camouflage, etc.