Performance optimization in pump-management entanglement distribution network via polarization manipulation

Abstract As a critical infrastructure for quantum internet, quantum entanglement distribution networks enable diverse quantum information applications. Among the existing architectures, the pump-management entanglement distribution network scheme exhibits remarkable scalability, functionality, and reconfigurability. However, its performance is hampered by the noise photons from concurrent spontaneous four-wave mixing (SFWM) processes and the unbalanced secure key rates (SKRs) across the network. Here, we propose a polarization manipulation scheme for pump-management entanglement distribution networks, enabling active control over the polarization states of the pump lasers and the generated single photons to optimize network performance. By utilizing orthogonally polarized pumps and polarization selection, the noise photons from other SFWM processes are effectively suppressed while preserving target entangled pairs, thereby significantly enhancing the SKR. Furthermore, our approach leverages the intrinsic efficiency differences of SFWM processes and a time-sharing method to achieve key rate equalization across the network. The performance enhancement is analyzed through theoretical analysis and numerical simulation. Our work resolves key bottlenecks in pump-management entanglement distribution networks, as well as establishes a powerful paradigm for performance optimization in future large-scale quantum networks.