{"paper":{"title":"Robust High-Precision Time Transfer over 91-km Hollow-Core Fiber: Immunity to Dispersion and Nonlinearity","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Hollow-core fiber supports high-precision time transfer over 91 km with time deviations below 80 ps by minimizing dispersion and nonlinearity effects.","cross_cats":[],"primary_cat":"physics.optics","authors_text":"Bo Liu, Huibo Hong, Jiang Chen, Qian Zhou, Rongduo Lu, Ruifang Dong, Ru Yuan, Shougang Zhang, Tao Liu, Xiang Zhang, Xinxing Guo","submitted_at":"2026-05-13T09:49:26Z","abstract_excerpt":"To address the fundamental limitations imposed by chromatic dispersion and environmental susceptibility in standard single-mode fiber (SMF) for long-haul high-precision time transfer, we systematically explore the application potential of hollow-core fiber (HCF) through comparative experiments. We designed a bidirectional time transfer platform enabling direct comparison between HCF and SMF links across distances of 91 km, 68 km, and 54 km. We quantitatively characterize the impact of critical non-reciprocal error sources, specifically the optical Kerr effect and chromatic dispersion, under va"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"Over the 91 km link, the HCF yields a signal-to-noise ratio (SNR) enhancement of more than 24 dB and confines the time deviation to less than 80 ps, which is nearly an order-of-magnitude improvement over SMF, where the time deviation exceeds 600 ps, while remaining nearly immune to power and wavelength fluctuations.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The bidirectional time transfer platform provides equivalent non-reciprocal error sources and environmental exposure for both fiber types, with no unaccounted setup-specific biases affecting the HCF versus SMF comparison.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Hollow-core fiber achieves time transfer stability of 0.2 ps at 1000 s over 91 km with time deviation under 80 ps, showing immunity to dispersion and nonlinearity compared to single-mode fiber.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Hollow-core fiber supports high-precision time transfer over 91 km with time deviations below 80 ps by minimizing dispersion and nonlinearity effects.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"bc8bfccfb4fa7ac66c29d98da2966326f5b7b3b6af5974d65001f55cf5b5d251"},"source":{"id":"2605.13272","kind":"arxiv","version":1},"verdict":{"id":"051ffb56-77cd-4c00-8feb-a5cbfa8cb21c","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T18:40:57.799412Z","strongest_claim":"Over the 91 km link, the HCF yields a signal-to-noise ratio (SNR) enhancement of more than 24 dB and confines the time deviation to less than 80 ps, which is nearly an order-of-magnitude improvement over SMF, where the time deviation exceeds 600 ps, while remaining nearly immune to power and wavelength fluctuations.","one_line_summary":"Hollow-core fiber achieves time transfer stability of 0.2 ps at 1000 s over 91 km with time deviation under 80 ps, showing immunity to dispersion and nonlinearity compared to single-mode fiber.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The bidirectional time transfer platform provides equivalent non-reciprocal error sources and environmental exposure for both fiber types, with no unaccounted setup-specific biases affecting the HCF versus SMF comparison.","pith_extraction_headline":"Hollow-core fiber supports high-precision time transfer over 91 km with time deviations below 80 ps by minimizing dispersion and nonlinearity effects."},"references":{"count":30,"sample":[{"doi":"10.1109/access.2025.3555493","year":2025,"title":"State-of-the-Art Review: Electronic Warfare Against Radar Systems,","work_id":"293b3c7b-7ea5-495f-bf7c-cf5f425eb7ad","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.3390/aerospace12110982","year":2025,"title":"Radiometric Interferometry for Deep Space Navigation Using Geostationary Satellites,","work_id":"e0a2df4d-f8e8-45bb-8861-42d712ac12eb","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1007/s10686-025-09989-5","year":2025,"title":"Simultaneous multi-spacecraft observations with VLBI radio telescopes to study the interplanetary phase scintillation,","work_id":"ad7bbfde-f54a-48bf-b99f-7380d563561b","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1016/j.asr.2023.06.021","year":2023,"title":"On the improvement of the sensitivity levels of VLBI solutions from a combination with GNSS,","work_id":"4c96252a-e623-472f-9df9-5edac40186ff","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1109/jlt.2023.3323434","year":2024,"title":"Quantum Two-Way Time Transfer Over a 103-km Urban Fiber Link","work_id":"3c2151d2-69b3-4c4d-a90c-df5c192bf847","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":30,"snapshot_sha256":"5749104b35beaca70e12ef86d8236ddf5ed31a99484e2b05fee7b53889f39103","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}