Real-Time, Dual-Physical-Layer Encryption Directly within an Optical Sensor on a Silicon Platform.

Today, data breaches pose a significant risk, especially those related to image data. Ideally, toward ultimate security, the image encryption should occur at the same time when the image is captured, directly within the sensor. Nonetheless, such optical sensors have not yet been achieved, limited by the physical properties of existing devices. Herein, we demonstrate a pioneer optical sensor that allows real-time, dual-physical-layer encryption directly within the sensor, enabled by the merits of III-nitride nanowires and careful engineering of the photocarrier dynamics within the nanowire heterojunctions. The robustness of the encryption is further tested against deep-learning-assisted cyber-attacks. Self-powered operation is also possible for such devices, representing a reduced energy cost for encryption. Moreover, the sensors are built directly on silicon (Si), making the technology compatible with existing Si electronics platforms. The simple epitaxy process of fabricating such sensors also means reduced time and production costs. This study represents a paradigm shift in image encryption research.