An 8-Channel Time-Tagger for Coincidence Measurement in Quantum Photonics Applications

Precise time measurement and event correlation have gained a prominent role in a large variety of quantum photonics
applications, including quantum communication, quantum simulation, and quantum computing. The increasing
complexity and scale of quantum photonic systems, particularly those capable of generating, manipulating, and
detecting single photons, necessitate advanced electronic timing systems that can accurately capture coincidence
events across multiple channels. A highly effective approach for measuring the time of arrival of a photon, detected
by single-photon detectors such as single-photon avalanche diodes (SPADs) or superconducting nanowires, is
the cascading of a time-to-amplitude converter (TAC) with an analog-to-digital converter (ADC), a configuration
distinguished by its high precision and linearity. In this work, we present a novel 8-channel time-tagger featuring an ASIC 8-channel TAC implemented in 350-nm Si-Ge technology.