{"artifact_id":"L1-922","layer":"L1","title":"Quantum Networks — Entanglement Distribution & Repeaters","domain":"Quantum Networking","sub_domain":"Quantum Repeaters","physics_fingerprint":{"title":"Quantum Networks — Entanglement Distribution & Repeaters","domain":"Quantum Networking","chapter":"Ch.12 Quantum Technology","sub_domain":"Quantum Repeaters","forward_model":"Entanglement-distribution rate over a repeater chain: direct transmission decays as R∝e^{−L/L_att}; n-segment repeaters with memories restore a polynomial scaling set by swap success and memory coherence.","challenge_blurb":"Build a quantum internet — distribute entanglement over continental distances by beating fibre loss with repeaters and memories.","challenge_group":"quantum","challenge_short":"Quantum Networks & Repeaters","grand_challenge":true,"governing_equation":"R_direct ∝ η = e^{−L/L_att};   R_repeater ∝ (η^{1/n})·p_swap^{n−1}·f(τ_mem)"},"observable_profile":{"unit":"entangled pairs/s at 1000 km (higher better)","floor":1.0,"metric":"ent_rate","sota_reference":"Memory-based repeater links (quantum-network testbeds, Delft/Hefei)"},"size_tiers":{"segments":[1,4,16],"distance_km":[100,1000,4000]},"hardness_fn":{"type":"grand_challenge","metric":"ent_rate","baseline":"Direct transmission (no repeater)","delta_tier":50},"initiator_dataset":[{"name":"Repeater-chain link-budget corpus","weight":0.6,"ipfs_cid":null,"license_hash":null},{"name":"Quantum-memory coherence dataset","weight":0.4,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":5000.0,"chain_hash":null,"chain_tx_hash":null,"chain_block":null}