Hanha Yan

Noise-robust entanglement indicator for two-qubit mixed states: Engineering design for real-time monitoring in noisy quantum key distribution

Real-time monitoring of weak entanglement in noisy fiber links is a practical bottleneck for entanglement-based quantum key distribution (QKD). Standard concurrence and negativity vanish with vanishing gradient near the separability boundary and are not optimized for hardware-level line-rate monitoring. We propose a cl...