CC BY 4.0Blasl, MartinMartinBlaslNamdari, MeysamMeysamNamdariWagner, MaximilianMaximilianWagnerGrahmann, JanJanGrahmann2025-11-052025-11-052024https://publica.fraunhofer.de/handle/publica/498779https://doi.org/10.24406/publica-607410.1117/1.JOM.4.3.03400110.24406/publica-60742-s2.0-85206125376To improve data security and authentication, we designed and fabricated a cryptographic key generator based on a photonic integrated circuit that converts a digital input key into a digital output key by means of a physical unclonable function (PUF). The PUF is realized by an imperfect multi-mode interferometer controlled by low-power micro-electromechanical system (MEMS) phase shifters. An analytical model was derived and used to prove the randomness of the generated digital keys, and the model was validated by measurements of a first proof-of-concept demonstrator. The demonstrator was fabricated using a silicon nitride photonic integrated circuit (PIC) platform and our recently developed MEMS-on-PIC technology.entruekey generatormicro-electromechanical systemsphotonic integrated circuitsilicon nitridejournal article