A fiber-based fully modular entangled-photon source architecture designed for scalable future quantum networks
We present the development, characterization, and evaluation of a modular, plug-and-play fiber-based entangled-photon source architecture for scalable industrial quantum networks. The design enables flexible integration and straightforward expansion within complex photonic infrastructures. Light collection is achieved using commercially available 780HP optical fibers coupled to monolithic microlenses and GaAs quantum dots, providing efficient photon extraction together with strong mechanical stability for reliable long-term operation. Combined with an optimized detection system, the source achieves a detected photon count rate of 2.13±0.03 MHz across four superconducting nanowire single-photon detector (SNSPD) channels and a peak entanglement fidelity of 97.0(3)% within an 8-ps temporal window. Comparative measurements using different optical configurations show only minor fidelity deviations of approximately 2%, demonstrating the robustness and reproducibility of the architecture. These results demonstrate the suitability of the proposed platform for scalable and deployable quantum communication systems.