Five-dimensional unclonable anticounterfeiting orthogonal Raman labels

Abstract

The physical unclonable function (PUF) is a cornerstone of information security. Encoding capacity and information density strongly relies on the encoding dimensions of PUF security labels. We herein report the design of orthogonal gap-enhanced Raman tags (O-GERTs) with ultrahigh brightness down to a single-particle level and excellent photostability for a PUF security label by randomly placing O-GERTs into polymer micropatterns. With near-infrared optical excitation, we demonstrate five-dimensional (namely, frequency, intensity and three-dimensional spaces) PUF labels with a super large encoding capacity (∼10⁵⁸⁵²) and an ultrahigh information density (∼10⁵⁸⁴⁴ Tbit cm⁻³). These PUF labels are digitized from the signals of embedded alkyne Raman reporters in the Raman-silent region, which are anti-interference with the polymer background. Authentication and mechanical bending experiments have revealed the robustness of the PUF labels. Furthermore, microfluidic SlipChip allows rapid (∼10 min) and high-throughput (tens of thousands of units per run) mass production of the labels. Due to the compact micron-scale footprint, these ultrathin PUF labels are finally integrated with Quick Response (QR) codes to afford double-layer information anticounterfeiting.