{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:WHOIQWULVUQR3XSFLXIRRWQIZH","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":"74f57f00e65b53dca70c0a6f3a7c3411a342a74016fe789b869269c168e5f44c","cross_cats_sorted":["physics.atom-ph","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2018-05-25T14:00:13Z","title_canon_sha256":"98f5197e062b6033f80d646181f9009e53a78ed4f8a2ebcc284295d66d5e43a2"},"schema_version":"1.0","source":{"id":"1805.10162","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.10162","created_at":"2026-05-18T00:00:55Z"},{"alias_kind":"arxiv_version","alias_value":"1805.10162v1","created_at":"2026-05-18T00:00:55Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.10162","created_at":"2026-05-18T00:00:55Z"},{"alias_kind":"pith_short_12","alias_value":"WHOIQWULVUQR","created_at":"2026-05-18T12:32:59Z"},{"alias_kind":"pith_short_16","alias_value":"WHOIQWULVUQR3XSF","created_at":"2026-05-18T12:32:59Z"},{"alias_kind":"pith_short_8","alias_value":"WHOIQWUL","created_at":"2026-05-18T12:32:59Z"}],"graph_snapshots":[{"event_id":"sha256:5b9d1d5d2748ea9398a1eba83e4de9b4b72db108e2184e45e15607aeae7fbec7","target":"graph","created_at":"2026-05-18T00:00:55Z","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 present a simple, robust, narrow-linewidth, frequency-doubled semiconductor laser source suitable for laser cooling and repumping of $^9$Be$^+$ ions. A distributed Bragg reflector (DBR) laser diode operating at 626 nm is self-injection-locked to a frequency doubling cavity via phase-stabilised optical feedback when the laser is resonant with the cavity mode. The short-term laser instability is reduced from the MHz-level to approximately 20 kHz by the injection process, thus eliminating the need for a high-bandwidth feedback loop to suppress the otherwise troublesome high-frequency laser noi","authors_text":"Piet O. Schmidt, Premjith Thekkeppatt, Steven A. King, Tobias Leopold","cross_cats":["physics.atom-ph","physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2018-05-25T14:00:13Z","title":"A self-injection locked DBR laser for laser cooling of beryllium ions"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.10162","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":"sha256:5d0afed60136d24775dcaebd81d68bc291cb82b6df5fb6c94f8246847f9c965e","target":"record","created_at":"2026-05-18T00:00:55Z","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":"74f57f00e65b53dca70c0a6f3a7c3411a342a74016fe789b869269c168e5f44c","cross_cats_sorted":["physics.atom-ph","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2018-05-25T14:00:13Z","title_canon_sha256":"98f5197e062b6033f80d646181f9009e53a78ed4f8a2ebcc284295d66d5e43a2"},"schema_version":"1.0","source":{"id":"1805.10162","kind":"arxiv","version":1}},"canonical_sha256":"b1dc885a8bad211dde455dd118da08c9f070bef2658b341dd6ce5dac625c5714","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b1dc885a8bad211dde455dd118da08c9f070bef2658b341dd6ce5dac625c5714","first_computed_at":"2026-05-18T00:00:55.620976Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:00:55.620976Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ky7EGL8OH2R5termNoX/4qpvDsJeYBsUTRyAW1ntmJFH328RMctgCK0inzfOioXHB8dYwoWII8N72RVOudQ9Aw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:00:55.621420Z","signed_message":"canonical_sha256_bytes"},"source_id":"1805.10162","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5d0afed60136d24775dcaebd81d68bc291cb82b6df5fb6c94f8246847f9c965e","sha256:5b9d1d5d2748ea9398a1eba83e4de9b4b72db108e2184e45e15607aeae7fbec7"],"state_sha256":"30adacec7866f3c71c7564136c62061a25af152f302b8adadacea8800f67b51c"}