260-Mile Quantum Memory Fiber Link Simulator

Optical Fiber Span (0 → 260 Miles / 418.4 km) 4 Nodes Active

Alice (Node 0: Hefei) Wavelength: 1550 nm (Telecom C-Band) Bob (Node N: Intercity Terminal)

Direct Fiber Attenuation 75.2 dB Without quantum repeaters

Per-Segment Loss 15.0 dB 52.0 mi per node

Entanglement Generation Rate 18.4 Hz Raw coincidence counts

Quantum Bit Error Rate (QBER) 3.8% Threshold < 11% for QKD

Bell State Measurement (Φ⁺ Entanglement Fidelity) 0.912 (PASS)

Min Valid: 0.850

Architecture Presets

Hardware Parameters

Repeater Stations 4 nodes

Frequency Conversion Eff. 85%

Memory Coherence Time 120 ms

Fiber Attenuation (dB/km) 0.18 dB/km

Detector Dark Count Rate 10 Hz

Telemetry Ledger

Total Distance	260.0 miles (418.4 km)
Photon Transit Time	2.09 ms
Memory Store Time vs Coherence	1.7%
Swapping Success Prob.	72.3%
Link Entanglement Status	STABLE LINK