Optically engineered physical unclonable functions

Abstract

Hardware and data security is a major concern in modern information network becoming complexed and closely linked in worldwide. The security level of digital identity and data privacy depends on cryptographic primitives. Device and person identifiers for authentication should be unique and complicated to avoid being copied or guessed, and information communications require cryptographic keys. Such cryptographic primitives can offer strong security by utilizing hidden keys. In this regard, a physically unclonable function (PUF) can be a useful approach to achieve high security. The PUFs act as ’digital fingerprints’ where information is retrieved from a system’s static entropy and prevent a malevolent party from producing an illegal copy. In this thesis, to boost the practical applicability, an optical PUF composed of a zinc oxide nanowire and gain material with random lasing properties is presented. Second, to improve conventional optical PUFs employing general reflecting media, an optical PUF using edible materials with various spectrum information is suggested. Finally, to resolve the limitations in conventional optical PUFs, such as bulkiness and high fabrication cost, an optical PUF using fibrous media is newly proposed with various optical analyses and implementation methods.