{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:2PURQGE7GSTJPKJ7O25HU5EJRJ","short_pith_number":"pith:2PURQGE7","canonical_record":{"source":{"id":"1904.11464","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2019-04-25T17:16:15Z","cross_cats_sorted":[],"title_canon_sha256":"d3b71caa9fa6100871774123a4e33e6c2468e00045f59ffc231761ac1adfbbfa","abstract_canon_sha256":"044c032f03776be3d0b2002c085618800e7281453543a10aeb74b5fe9d6811eb"},"schema_version":"1.0"},"canonical_sha256":"d3e918189f34a697a93f76ba7a74898a78317bbadb56fe5a2e32cf82f3cfa027","source":{"kind":"arxiv","id":"1904.11464","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1904.11464","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"arxiv_version","alias_value":"1904.11464v2","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1904.11464","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"pith_short_12","alias_value":"2PURQGE7GSTJ","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"2PURQGE7GSTJPKJ7","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"2PURQGE7","created_at":"2026-05-18T12:33:07Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:2PURQGE7GSTJPKJ7O25HU5EJRJ","target":"record","payload":{"canonical_record":{"source":{"id":"1904.11464","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2019-04-25T17:16:15Z","cross_cats_sorted":[],"title_canon_sha256":"d3b71caa9fa6100871774123a4e33e6c2468e00045f59ffc231761ac1adfbbfa","abstract_canon_sha256":"044c032f03776be3d0b2002c085618800e7281453543a10aeb74b5fe9d6811eb"},"schema_version":"1.0"},"canonical_sha256":"d3e918189f34a697a93f76ba7a74898a78317bbadb56fe5a2e32cf82f3cfa027","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:42:41.770919Z","signature_b64":"0S9MxqC+MShszkWvvh4lT1/zbTZrnkeW5boNa8x3mn+WdO6BRN3Z0UViYMP5/JkrA2E8w42N6iMEy7LhINcOAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"d3e918189f34a697a93f76ba7a74898a78317bbadb56fe5a2e32cf82f3cfa027","last_reissued_at":"2026-05-17T23:42:41.770216Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:42:41.770216Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1904.11464","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:42:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"3yMXNrIfeJ1j/gseWILQWhRxRYxQZsSQFK3/kCotUUxBMjAHHgsHNbw0devX2cBqopoKDlcKYqc6ZvuaZ6G7Bw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-11T22:10:21.433714Z"},"content_sha256":"05a617251a9248e52b2787ea9e2908ff8c81c0ca419104f64030bc10c5446c80","schema_version":"1.0","event_id":"sha256:05a617251a9248e52b2787ea9e2908ff8c81c0ca419104f64030bc10c5446c80"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:2PURQGE7GSTJPKJ7O25HU5EJRJ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Observation of Unidirectional Bound States in the Continuum Enabled by Topological Defects","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"physics.optics","authors_text":"Bo Zhen, Chao Peng, Jicheng Jin, Marin Solja\\v{c}i\\'c, Xuefan Yin","submitted_at":"2019-04-25T17:16:15Z","abstract_excerpt":"Unidirectional radiation is important for a variety of optoelectronic applications. Many unidirectional emitters exist, but they all rely on the use of materials or structures that forbid outgoing waves, i.e. mirrors. Here, we theoretically propose and experimentally demonstrate a class of resonances in photonic crystal slabs, which only radiate towards a single side with no mirror placed on the other side - we call them ``unidirectional bound states in the continuum\". These resonances are found to emerge when a pair of half-integer topological charges in the polarization field bounce into eac"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1904.11464","kind":"arxiv","version":2},"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":"2026-05-17T23:42:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"jS+TMC21fCYbSOuIvcVI79OtmrjWOlgyC89hbWyA4ry5MrzmPYaxahJFwy994kHI/eQZnT6mI5a62w9ZRKwLBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-11T22:10:21.434373Z"},"content_sha256":"f76ba68b5a1640432dd235a0ceaf225628f371513c49128ff3f9c9988c61d8fd","schema_version":"1.0","event_id":"sha256:f76ba68b5a1640432dd235a0ceaf225628f371513c49128ff3f9c9988c61d8fd"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/bundle.json","state_url":"https://pith.science/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/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":"2026-06-11T22:10:21Z","links":{"resolver":"https://pith.science/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ","bundle":"https://pith.science/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/bundle.json","state":"https://pith.science/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/2PURQGE7GSTJPKJ7O25HU5EJRJ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:2PURQGE7GSTJPKJ7O25HU5EJRJ","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":"044c032f03776be3d0b2002c085618800e7281453543a10aeb74b5fe9d6811eb","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2019-04-25T17:16:15Z","title_canon_sha256":"d3b71caa9fa6100871774123a4e33e6c2468e00045f59ffc231761ac1adfbbfa"},"schema_version":"1.0","source":{"id":"1904.11464","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1904.11464","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"arxiv_version","alias_value":"1904.11464v2","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1904.11464","created_at":"2026-05-17T23:42:41Z"},{"alias_kind":"pith_short_12","alias_value":"2PURQGE7GSTJ","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"2PURQGE7GSTJPKJ7","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"2PURQGE7","created_at":"2026-05-18T12:33:07Z"}],"graph_snapshots":[{"event_id":"sha256:f76ba68b5a1640432dd235a0ceaf225628f371513c49128ff3f9c9988c61d8fd","target":"graph","created_at":"2026-05-17T23:42:41Z","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":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"Unidirectional radiation is important for a variety of optoelectronic applications. Many unidirectional emitters exist, but they all rely on the use of materials or structures that forbid outgoing waves, i.e. mirrors. Here, we theoretically propose and experimentally demonstrate a class of resonances in photonic crystal slabs, which only radiate towards a single side with no mirror placed on the other side - we call them ``unidirectional bound states in the continuum\". These resonances are found to emerge when a pair of half-integer topological charges in the polarization field bounce into eac","authors_text":"Bo Zhen, Chao Peng, Jicheng Jin, Marin Solja\\v{c}i\\'c, Xuefan Yin","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2019-04-25T17:16:15Z","title":"Observation of Unidirectional Bound States in the Continuum Enabled by Topological Defects"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1904.11464","kind":"arxiv","version":2},"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":"sha256:05a617251a9248e52b2787ea9e2908ff8c81c0ca419104f64030bc10c5446c80","target":"record","created_at":"2026-05-17T23:42:41Z","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":"044c032f03776be3d0b2002c085618800e7281453543a10aeb74b5fe9d6811eb","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2019-04-25T17:16:15Z","title_canon_sha256":"d3b71caa9fa6100871774123a4e33e6c2468e00045f59ffc231761ac1adfbbfa"},"schema_version":"1.0","source":{"id":"1904.11464","kind":"arxiv","version":2}},"canonical_sha256":"d3e918189f34a697a93f76ba7a74898a78317bbadb56fe5a2e32cf82f3cfa027","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"d3e918189f34a697a93f76ba7a74898a78317bbadb56fe5a2e32cf82f3cfa027","first_computed_at":"2026-05-17T23:42:41.770216Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:42:41.770216Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"0S9MxqC+MShszkWvvh4lT1/zbTZrnkeW5boNa8x3mn+WdO6BRN3Z0UViYMP5/JkrA2E8w42N6iMEy7LhINcOAA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:42:41.770919Z","signed_message":"canonical_sha256_bytes"},"source_id":"1904.11464","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:05a617251a9248e52b2787ea9e2908ff8c81c0ca419104f64030bc10c5446c80","sha256:f76ba68b5a1640432dd235a0ceaf225628f371513c49128ff3f9c9988c61d8fd"],"state_sha256":"1084ec18f10efe63a9a4f9068728a591b7001008de38e762655d7eaa51ef8641"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"PQsAVShGkmNKj6mk8L+XTLCMTjr0iIOWY/CVvv22MpJUT5t8cObjuDgkT/IzjVoFvTta0LkDgEtvvW7kJIYgDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-11T22:10:21.438242Z","bundle_sha256":"5c0166637357f38893d387fdefbf392f6391ecd0e440a964e93bbbe0ddf2b4d0"}}