{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:G2YRHATK4WNV4VP2DLGFEHO3ER","short_pith_number":"pith:G2YRHATK","canonical_record":{"source":{"id":"1906.08995","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2019-06-21T08:09:32Z","cross_cats_sorted":[],"title_canon_sha256":"b212a6d29b579717861b0f061135807685ffa17d9bc1c6c8e89355c3ddb08263","abstract_canon_sha256":"623e4bff30d075dec35c2f2a3cc072844c4e94d2f0d1e3403e91a7417c4088d9"},"schema_version":"1.0"},"canonical_sha256":"36b113826ae59b5e55fa1acc521ddb247371f3006b1a5745cd3017f545740f5a","source":{"kind":"arxiv","id":"1906.08995","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.08995","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"arxiv_version","alias_value":"1906.08995v1","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.08995","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"pith_short_12","alias_value":"G2YRHATK4WNV","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_16","alias_value":"G2YRHATK4WNV4VP2","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_8","alias_value":"G2YRHATK","created_at":"2026-05-18T12:33:18Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:G2YRHATK4WNV4VP2DLGFEHO3ER","target":"record","payload":{"canonical_record":{"source":{"id":"1906.08995","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2019-06-21T08:09:32Z","cross_cats_sorted":[],"title_canon_sha256":"b212a6d29b579717861b0f061135807685ffa17d9bc1c6c8e89355c3ddb08263","abstract_canon_sha256":"623e4bff30d075dec35c2f2a3cc072844c4e94d2f0d1e3403e91a7417c4088d9"},"schema_version":"1.0"},"canonical_sha256":"36b113826ae59b5e55fa1acc521ddb247371f3006b1a5745cd3017f545740f5a","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:42:47.142597Z","signature_b64":"/y940GUh7v3obSv9FRxf8oYas6GIbeuvBq/X5Il6LX63E0hf7vt7CbSobKsvTGj+/qGNx5FSFxgEXx9dWU4BAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"36b113826ae59b5e55fa1acc521ddb247371f3006b1a5745cd3017f545740f5a","last_reissued_at":"2026-05-17T23:42:47.141938Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:42:47.141938Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1906.08995","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:42:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"VJrsX0BO58oTByQVdpBotF0JCZowE7Xw4KtsKjBz1iYOjEEIMMtEXlnPCXEfW1ZpHa9Ah89+NMTv9s4xOd5xBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T18:16:08.510399Z"},"content_sha256":"ff6848b8cfdc49405edfdc4123d38bc36629ed5a4e303e75f2b34f71f8155c72","schema_version":"1.0","event_id":"sha256:ff6848b8cfdc49405edfdc4123d38bc36629ed5a4e303e75f2b34f71f8155c72"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:G2YRHATK4WNV4VP2DLGFEHO3ER","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A nearly optimal and robust protocol for nonlinear phase estimation using coherent states","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Chen-Fei Jin, Jian-dong Zhang, Jun-Yan Hu, Long-Zhu Cen, Yi-Fei Sun, Yuan Zhao, Zi-Jing Zhang","submitted_at":"2019-06-21T08:09:32Z","abstract_excerpt":"We propose a protocol for the second-order nonlinear phase estimation with a coherent state as input and balanced homodyne detection as measurement strategy. The sensitivity is sub-Heisenberg limit, which scales as $N^{-3/2}$ for $N$ photons on average. By ruling out hidden resources in quantum Fisher information, the fundamental sensitivity limit is recalculated and compared to the optimal sensitivity of our protocol. In addition, we investigate the effect of photon loss on sensitivity, and discuss the robustness of measurement strategy. The results indicate that our protocol is nearly optima"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.08995","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:42:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cEU4U1+dAT4cAFJptZ3CzpBy+dIdd4Yjba9d3jW/p8o8vUzVUVfcw/zY4ooq4YEyEjpVt7U6OsByZD7J1ft1BQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T18:16:08.511504Z"},"content_sha256":"7eb1da9525d1163422e2d320d868d07350e0edbb6d8e7d8cf11490cd326eb8ee","schema_version":"1.0","event_id":"sha256:7eb1da9525d1163422e2d320d868d07350e0edbb6d8e7d8cf11490cd326eb8ee"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/bundle.json","state_url":"https://pith.science/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-25T18:16:08Z","links":{"resolver":"https://pith.science/pith/G2YRHATK4WNV4VP2DLGFEHO3ER","bundle":"https://pith.science/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/bundle.json","state":"https://pith.science/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/state.json","well_known_bundle":"https://pith.science/.well-known/pith/G2YRHATK4WNV4VP2DLGFEHO3ER/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:G2YRHATK4WNV4VP2DLGFEHO3ER","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":"623e4bff30d075dec35c2f2a3cc072844c4e94d2f0d1e3403e91a7417c4088d9","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2019-06-21T08:09:32Z","title_canon_sha256":"b212a6d29b579717861b0f061135807685ffa17d9bc1c6c8e89355c3ddb08263"},"schema_version":"1.0","source":{"id":"1906.08995","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.08995","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"arxiv_version","alias_value":"1906.08995v1","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.08995","created_at":"2026-05-17T23:42:47Z"},{"alias_kind":"pith_short_12","alias_value":"G2YRHATK4WNV","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_16","alias_value":"G2YRHATK4WNV4VP2","created_at":"2026-05-18T12:33:18Z"},{"alias_kind":"pith_short_8","alias_value":"G2YRHATK","created_at":"2026-05-18T12:33:18Z"}],"graph_snapshots":[{"event_id":"sha256:7eb1da9525d1163422e2d320d868d07350e0edbb6d8e7d8cf11490cd326eb8ee","target":"graph","created_at":"2026-05-17T23:42:47Z","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 propose a protocol for the second-order nonlinear phase estimation with a coherent state as input and balanced homodyne detection as measurement strategy. The sensitivity is sub-Heisenberg limit, which scales as $N^{-3/2}$ for $N$ photons on average. By ruling out hidden resources in quantum Fisher information, the fundamental sensitivity limit is recalculated and compared to the optimal sensitivity of our protocol. In addition, we investigate the effect of photon loss on sensitivity, and discuss the robustness of measurement strategy. The results indicate that our protocol is nearly optima","authors_text":"Chen-Fei Jin, Jian-dong Zhang, Jun-Yan Hu, Long-Zhu Cen, Yi-Fei Sun, Yuan Zhao, Zi-Jing Zhang","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2019-06-21T08:09:32Z","title":"A nearly optimal and robust protocol for nonlinear phase estimation using coherent states"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.08995","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:ff6848b8cfdc49405edfdc4123d38bc36629ed5a4e303e75f2b34f71f8155c72","target":"record","created_at":"2026-05-17T23:42:47Z","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":"623e4bff30d075dec35c2f2a3cc072844c4e94d2f0d1e3403e91a7417c4088d9","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2019-06-21T08:09:32Z","title_canon_sha256":"b212a6d29b579717861b0f061135807685ffa17d9bc1c6c8e89355c3ddb08263"},"schema_version":"1.0","source":{"id":"1906.08995","kind":"arxiv","version":1}},"canonical_sha256":"36b113826ae59b5e55fa1acc521ddb247371f3006b1a5745cd3017f545740f5a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"36b113826ae59b5e55fa1acc521ddb247371f3006b1a5745cd3017f545740f5a","first_computed_at":"2026-05-17T23:42:47.141938Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:42:47.141938Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"/y940GUh7v3obSv9FRxf8oYas6GIbeuvBq/X5Il6LX63E0hf7vt7CbSobKsvTGj+/qGNx5FSFxgEXx9dWU4BAg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:42:47.142597Z","signed_message":"canonical_sha256_bytes"},"source_id":"1906.08995","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ff6848b8cfdc49405edfdc4123d38bc36629ed5a4e303e75f2b34f71f8155c72","sha256:7eb1da9525d1163422e2d320d868d07350e0edbb6d8e7d8cf11490cd326eb8ee"],"state_sha256":"184eec39010ff3b9fbbc9d150aa22889b6234d1075dfbca9875110e50b313ad1"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"EfwOS0XjIv7ym0A/dHz3iKZq7NBAqjeG6XADzfbQm8wMV4UHxlTFFpctPrlUFYUPKz5HIhWLjFk+njqh1HKFAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T18:16:08.515225Z","bundle_sha256":"e97822b04e827f2e71164dbc0d109e28ffeeb5f088354b1f491c8e4b7fc4d3a3"}}