Photonic Cryptographic Communication Interface Based on Quantum Well Diode

The Quantum well diode (QWD) serves as both a transmitter and receiver due to its capability of coexisting emission detection. In this experiment, we successfully implemented a single-chip, half-duplex optical communication encryption interface. By utilizing encrypted optical signals, we stimulated the QWD to generate activation signals, which were then decoded and identified by a microprocessor unit (MPU). This allowed audio signals to enter through the input-output (I/O) port and be emitted via the QWD. The results of this experiment validate that a single QWD can function as both a transmitter and receiver, providing sufficient bandwidth for audio transmission. This breakthrough presents a novel solution for intelligent sensing in the era of the Internet of Things (IoT).