Quantum Simulation of the Efficiency of the SPAD Detector for Space Applications

Abstract

Single-Photon Avalanche Diodes (SPADs) are critical components of emerging quantum communication networks, used to detect single photon. They are placed in satellites for longdistance communication and are susceptible to radiation-induced displacement damage in the space environment. This degrades their performance. In this work, SPAD is simulated in a space environment by introducing a quantum simulation framework that leverages second quantization and Fock space truncation to model the SPAD as a two-level (|g⟩,|e⟩), incorporating radiation damage through Lindblad open system dynamics. This approach differs significantly from conventional TCAD simulations, which rely on semiclassical approximations that fail to capture the discrete quantum statistics of single-photon interactions and the dynamics of trap states. In this work, Photon Detection Efficiency and timing jitter, in ideal and damping environments, are simulated as expectation values.