The rapid development of the Internet of Things and the digital information era has intensified the demand for secure hardware and information systems. Physical unclonable functions (PUFs) provide a hardware-based approach by exploiting fabrication-induced randomness to generate unique, unclonable labels. Concurrently, advances in deterministic nanofabrication increasingly challenge the unclonability of conventional micro- and nanoscale PUFs, motivating the exploration of more fundamental sources of physical randomness. Here, we demonstrate an atomic-scale PUF architecture that leverages intrinsic randomness in solids through lattice and defect engineering. The resulting PUFs exhibit both three-dimensional spatial variability and atomic-scale configurational complexity, yielding extraordinary encoding space and uniqueness. For a characteristic feature size of 1 nanometer, the Shannon entropy is estimated at 17.49, underscoring the encoding capacity. Moreover, the embedded structure ensures intrinsic unclonability and robustness against environmental perturbations. These results establish atomic-scale PUFs as a fundamentally secure and scalable platform for next-generation hardware and information security.
Chai et al. (Wed,) studied this question.