{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:F4IXDNKAUXT5SZOH7ZBWST4K53","merge_version":"pith-open-graph-merge-v1","event_count":3,"valid_event_count":3,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"cf6593668c679fc923cc21df5a9e32a92b76633c05d7f4254688c2ad8c6686de","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-05-13T13:05:57Z","title_canon_sha256":"30d7c5e84555c64f6f3bb8c02af7ec135879d475da07337e0eda4150cd029913"},"schema_version":"1.0","source":{"id":"2605.13480","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2605.13480","created_at":"2026-05-18T02:44:41Z"},{"alias_kind":"arxiv_version","alias_value":"2605.13480v1","created_at":"2026-05-18T02:44:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2605.13480","created_at":"2026-05-18T02:44:41Z"},{"alias_kind":"pith_short_12","alias_value":"F4IXDNKAUXT5","created_at":"2026-05-18T12:33:37Z"},{"alias_kind":"pith_short_16","alias_value":"F4IXDNKAUXT5SZOH","created_at":"2026-05-18T12:33:37Z"},{"alias_kind":"pith_short_8","alias_value":"F4IXDNKA","created_at":"2026-05-18T12:33:37Z"}],"graph_snapshots":[{"event_id":"sha256:58efe176f700b5fad0800ac66a7e4fdcb1623371eecb4f7626afab54af7788a9","target":"graph","created_at":"2026-05-18T02:44:41Z","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":4,"items":[{"attestation":"unclaimed","claim_id":"C1","kind":"strongest_claim","source":"verdict.strongest_claim","status":"machine_extracted","text":"We observe a relative improvement of the readout contrast by 17 %, and infer a reduction of the initialization error of more than 50 %. ... a measurement speedup by a factor of >1.5 is extracted"},{"attestation":"unclaimed","claim_id":"C2","kind":"weakest_assumption","source":"verdict.weakest_assumption","status":"machine_extracted","text":"That the charge state purification by strong laser pulse followed by weak illumination reliably leads to higher spin polarization without introducing additional noise or decoherence in practical sensing sequences."},{"attestation":"unclaimed","claim_id":"C3","kind":"one_line_summary","source":"verdict.one_line_summary","status":"machine_extracted","text":"A two-step optical protocol using charge state dynamics boosts NV center spin contrast by 17% and reduces initialization error by over 50%."},{"attestation":"unclaimed","claim_id":"C4","kind":"headline","source":"verdict.pith_extraction.headline","status":"machine_extracted","text":"Charge state transitions in NV centers can be turned into a tool that raises spin readout contrast by 17 percent and cuts initialization error by more than half."}],"snapshot_sha256":"9e47b0953b75866c0627fa0b3fd0edc02ab083aae9ac73eedafcb0950c84a41e"},"formal_canon":{"evidence_count":1,"snapshot_sha256":"ec097031b2bca94f451c8d9036c800acad68143e7735c81621e3b8e23dee57a7"},"paper":{"abstract_excerpt":"We propose and experimentally demonstrate a method to strongly increase the sensitivity of spin measurements on nitrogen-vacancy (NV) centers in diamond, which can be readily implemented in existing quantum sensing experiments. While charge state transitions of this defect are generally considered a parasitic effect to be avoided, we show here that these can be used to significantly increase the NV center's spin contrast, a key quantity for high sensitivity magnetometry and high fidelity state readout. The protocol consists of a two-step procedure, in which the charge state of the defect is fi","authors_text":"Adam Gali, Daniel Wirtitsch, Fedor Jelezko, Georg Wachter, Michael Trupke, Michal Gulka, Milos Nesladek, Sarah Reisenbauer, Viktor Iv\\'ady","cross_cats":[],"headline":"Charge state transitions in NV centers can be turned into a tool that raises spin readout contrast by 17 percent and cuts initialization error by more than half.","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-05-13T13:05:57Z","title":"Exploiting ionization dynamics in the nitrogen vacancy center for rapid, high-contrast spin and charge state initialization"},"references":{"count":66,"internal_anchors":5,"resolved_work":66,"sample":[{"cited_arxiv_id":"1302.3288","doi":"","is_internal_anchor":true,"ref_index":1,"title":"The nitrogen-vacancy colour centre in diamond","work_id":"3dba386a-37fb-4e7b-8e9c-22c3b7fe7120","year":2013},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":2,"title":"Magnetometry with nitrogen-vacancy defects in diamond,","work_id":"33374263-1b60-4678-989a-6ea9f87a88fc","year":2014},{"cited_arxiv_id":"1304.1068","doi":"","is_internal_anchor":true,"ref_index":3,"title":"Nanometer scale quantum thermometry in a living cell","work_id":"bd7e18c9-48ea-42b9-8ed3-62905d86d1c6","year":2013},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":4,"title":"Electric- field sensing using single diamond spins,","work_id":"f1d94c5f-c507-4563-b3a2-66f86c8ffb72","year":2011},{"cited_arxiv_id":"","doi":"","is_internal_anchor":false,"ref_index":5,"title":"High-precision nanoscale temperature sensing using single defects in diamond,","work_id":"f22db47d-4d04-45fd-b3f9-43a4cff68e71","year":2013}],"snapshot_sha256":"873ee06c1af116a2745dd4f96d5eb2877cf4b7787e6682472c33ed06e836f67a"},"source":{"id":"2605.13480","kind":"arxiv","version":1},"verdict":{"created_at":"2026-05-14T20:12:37.242876Z","id":"6f012070-c4da-4a35-b425-69a4b81c7e4d","model_set":{"reader":"grok-4.3"},"one_line_summary":"A two-step optical protocol using charge state dynamics boosts NV center spin contrast by 17% and reduces initialization error by over 50%.","pipeline_version":"pith-pipeline@v0.9.0","pith_extraction_headline":"Charge state transitions in NV centers can be turned into a tool that raises spin readout contrast by 17 percent and cuts initialization error by more than half.","strongest_claim":"We observe a relative improvement of the readout contrast by 17 %, and infer a reduction of the initialization error of more than 50 %. ... a measurement speedup by a factor of >1.5 is extracted","weakest_assumption":"That the charge state purification by strong laser pulse followed by weak illumination reliably leads to higher spin polarization without introducing additional noise or decoherence in practical sensing sequences."}},"verdict_id":"6f012070-c4da-4a35-b425-69a4b81c7e4d"}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:520bd3afee366bca767bf63938e3c5ceeaa608dd200e34f7112b33e12a83b7be","target":"record","created_at":"2026-05-18T02:44:41Z","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":"cf6593668c679fc923cc21df5a9e32a92b76633c05d7f4254688c2ad8c6686de","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"quant-ph","submitted_at":"2026-05-13T13:05:57Z","title_canon_sha256":"30d7c5e84555c64f6f3bb8c02af7ec135879d475da07337e0eda4150cd029913"},"schema_version":"1.0","source":{"id":"2605.13480","kind":"arxiv","version":1}},"canonical_sha256":"2f1171b540a5e7d965c7fe43694f8aeedfd8a17287168373f414d453b8231c33","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2f1171b540a5e7d965c7fe43694f8aeedfd8a17287168373f414d453b8231c33","first_computed_at":"2026-05-18T02:44:41.387825Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:44:41.387825Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"dXGAe+iu7QVhlFubISUQtt/iTyz2OZ84If7SFp3fel73d2VkxRB+o4Rfg4JzCBOBrNaARpGWyXKruLb1WB36Aw==","signature_status":"signed_v1","signed_at":"2026-05-18T02:44:41.388332Z","signed_message":"canonical_sha256_bytes"},"source_id":"2605.13480","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:520bd3afee366bca767bf63938e3c5ceeaa608dd200e34f7112b33e12a83b7be","sha256:58efe176f700b5fad0800ac66a7e4fdcb1623371eecb4f7626afab54af7788a9","sha256:087582f29b69bcf9cc970b4dc9b9ed42b8fa84fd4115bfb13dd12f2cfe335992"],"state_sha256":"7241f576b8a20486f57ebb3ea7438ea518fbc35a54e2d0d9179f35a37d867554"}