{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:OXGLR4OWVTVLXIB4H3N2DGLUJZ","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"72f9395d5d9e9e2965e1c71b6782b6715fcd9b983c1602a01a34409f172b147a","cross_cats_sorted":["physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2014-08-26T00:45:26Z","title_canon_sha256":"b3b17334e501e87a4734f4d66731a456aa8335ca83b17c4759e2782421e0e081"},"schema_version":"1.0","source":{"id":"1408.5953","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1408.5953","created_at":"2026-05-18T02:44:15Z"},{"alias_kind":"arxiv_version","alias_value":"1408.5953v1","created_at":"2026-05-18T02:44:15Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1408.5953","created_at":"2026-05-18T02:44:15Z"},{"alias_kind":"pith_short_12","alias_value":"OXGLR4OWVTVL","created_at":"2026-05-18T12:28:43Z"},{"alias_kind":"pith_short_16","alias_value":"OXGLR4OWVTVLXIB4","created_at":"2026-05-18T12:28:43Z"},{"alias_kind":"pith_short_8","alias_value":"OXGLR4OW","created_at":"2026-05-18T12:28:43Z"}],"graph_snapshots":[{"event_id":"sha256:34ed32a882c6960492840831063f66eadd4d60f945859ebdb64de0895a5a8713","target":"graph","created_at":"2026-05-18T02:44:15Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"We report the ultrafast laser fabrication and mid-IR characterization (3.39 microns) of four-port evanescent field directional couplers. The couplers were fabricated in a commercial gallium lanthanum sulphide glass substrate using sub-picosecond laser pulses of 1030 nm light. Straight waveguides inscribed using optimal fabrication parameters were found to exhibit propagation losses of 0.8 dB/cm. A series of couplers were inscribed with different interaction lengths, and we demonstrate power splitting ratios of between 8% and 99% for mid-IR light with a wavelength of 3.39 microns. These results","authors_text":"Alexander Arriola, Debaditya Choudhury, Lucas Labadie, Robert R. Thomson, Sebabrata Mukherjee","cross_cats":["physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2014-08-26T00:45:26Z","title":"Ultrafast laser inscription of mid-IR directional couplers for stellar interferometry"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1408.5953","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:89d38ad9f88d86a80a6ae39203eb55c6bd0d63fc993ebd47c30c07db4142e22c","target":"record","created_at":"2026-05-18T02:44:15Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"72f9395d5d9e9e2965e1c71b6782b6715fcd9b983c1602a01a34409f172b147a","cross_cats_sorted":["physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2014-08-26T00:45:26Z","title_canon_sha256":"b3b17334e501e87a4734f4d66731a456aa8335ca83b17c4759e2782421e0e081"},"schema_version":"1.0","source":{"id":"1408.5953","kind":"arxiv","version":1}},"canonical_sha256":"75ccb8f1d6aceabba03c3edba199744e4eaec7b5d3c9154feaf786aced84a82e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"75ccb8f1d6aceabba03c3edba199744e4eaec7b5d3c9154feaf786aced84a82e","first_computed_at":"2026-05-18T02:44:15.791901Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:44:15.791901Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"3ASaGdsfXHcHHYWjmsguXjkbCalDJ2H38VhARkF5XXNEvz7+7Ow8x2vV4A8OyLAyBWtSRT6kAIfkPXrThtVkDg==","signature_status":"signed_v1","signed_at":"2026-05-18T02:44:15.792408Z","signed_message":"canonical_sha256_bytes"},"source_id":"1408.5953","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:89d38ad9f88d86a80a6ae39203eb55c6bd0d63fc993ebd47c30c07db4142e22c","sha256:34ed32a882c6960492840831063f66eadd4d60f945859ebdb64de0895a5a8713"],"state_sha256":"8ebb0dbd3030df0dddd4e43d08540436b1c73e667038aae2a66251db7338de1c"}