“…During the past decade, many efforts have been undertaken to produce strong and attack resistant PUFs using a broad combination of materials and physical phenomena. Such combination has led to the development of composite systems with unique physical and chemical properties that can be detected at different scales and only using specific experimental techniques allowing multilevel encryption. , From the pioneering work of Pappu et al that presented the first example of an optical PUF, a plethora of solutions have been proposed on the basis of organic crystals, photonic crystals, fluorescent materials, perovskites, metamaterials, soft materials, and polymers, which offer peculiar optical properties and random morphologies led, for example, by the self-assembling properties of some materials. ,− Recent technologies based on plasmonic security tags or biomimetic microfingerprints achieved high levels of protection against cloning attacks. , The paradox is, however, that many of the strongest anticounterfeiting systems can be more expensive than the protected products. Moreover, specific and expensive tools are usually required to verify their authenticity.…”