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    "headline": "Four Photons Shared 750 Secret Bits Each Second",
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    "dek": "A four-arm, 20-kilometer fiber network supported composable protection against outside and participant attacks.",
    "summary": "A four-arm, 20-kilometer fiber network supported composable protection against outside and participant attacks.",
    "body_text": "Two engineered photon-pair sources generated four-qubit GHZ states at more than 5,000 fourfold events per second. Distributed across a four-arm star network totaling 20 km of fiber, the setup reached a maximum asymptotic secret-key rate of 750 ± 10 bits per second. From measured rates and errors, the authors infer an 8.7-megabit finite-key lower bound for an optimized 24-hour run if device statistics remain stationary.",
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      "From measured rates and errors, the authors infer an 8.7-megabit finite-key lower bound for an optimized 24-hour run if device statistics remain stationary."
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    "tags": [
      "quantum networks",
      "secret sharing",
      "GHZ states"
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      "source_id": "source-2026-09-15-018",
      "title": "arXiv preprint 2609.13367",
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