This invention presents a method for all-optical readout of detection events from on-chip photodetectors (PDs) using Mach-Zehnder Interferometers (MZIs). It eliminates the need for electrical wiring to transmit detection signals by leveraging optical modulation, providing a fully photonic detection and readout scheme. The system uses an integrated on-chip laser that serves as a common optical source, splitting light into multiple channels to feed each MZI. The MZI, connected to a photodetector, registers detection events via phase shifts, and the output is spatially resolved using grating couplers. The method is scalable, thermally efficient, and compatible with standard photonic integrated circuit (PIC) fabrication, making it suitable for a wide range of applications, including quantum photonics, LiDAR, and optical computing. Background: In many advanced photonic systems, such as quantum photonics, LiDAR, and optical computing, the need for electrical wiring for signal transmission introduces limitations. For example, In cryogenic quantum experiments, electrical wiring introduces thermal load, while in high-speed rotating systems, it requires complex slip rings. This invention seeks to overcome these limitations by using optical methods for signal detection and readout, eliminating the need for electrical wiring that could otherwise introduce thermal loads or slow performance. Applications:
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