From device to dynamics: an iterative architectural framework for high-performance single-photon detection at room...

Photon detection is a cornerstone of quantum optics, traditionally regarded as a device-level operation constrained by the intrinsic properties of single-photon detectors (SPDs). Consequently, high-performance detection has relied heavily on superconducting technologies, whose cryogenic requirement imposes significant infrastructure burdens and limits scalable deployment. To circumvent these constraints, we propose the enhanced single-photon detection (ESPD) framework. It shifts photon detection from device-centric optimization to an integrated quantum-information-processing task, where detection performance is governed by an iterative dynamical system. This architecture enables systematic performance upgrades through architectural design rather than material modification, allowing high-performance detection with exclusively room-temperature hardware. Through rigorous theoretical analysis and numerical simulations grounded in physical parameters, we show that the ESPD dynamics converge toward a high-performance steady state, starting with a legacy SPD. Specifically, the framework can upgrade a low-performance SPD to achieve an effective detection efficiency (DE) exceeding 93% and a dark count rate (DCR) below 10^-9, comparable to state-of-the-art superconducting SPDs, and significantly relaxes the transmission rate constraints for quantum communication. While physical realization requires further integration efforts, this work establishes a rigorous theoretical foundation for high-performance room-temperature photon detection and provides a general methodology for transcending device-level constraints in broader quantum technologies. Codes are available at https://github.com/Hao-B-Shu/ESPD.