{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:3JH3QO7PJFCWBHB65HTBP77WRU","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":"8cce5dc4c18cf6f1ad521ee539cfe8b413536f0fa2d4b3f16ead86b0c20d84c2","cross_cats_sorted":["cond-mat.mes-hall"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-02-26T10:44:15Z","title_canon_sha256":"0e2fa171680062544d686f9c97048d2f9f39a26a5a35a23d6ec8eacbd52abf00"},"schema_version":"1.0","source":{"id":"1302.6389","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1302.6389","created_at":"2026-05-18T03:18:06Z"},{"alias_kind":"arxiv_version","alias_value":"1302.6389v1","created_at":"2026-05-18T03:18:06Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1302.6389","created_at":"2026-05-18T03:18:06Z"},{"alias_kind":"pith_short_12","alias_value":"3JH3QO7PJFCW","created_at":"2026-05-18T12:27:32Z"},{"alias_kind":"pith_short_16","alias_value":"3JH3QO7PJFCWBHB6","created_at":"2026-05-18T12:27:32Z"},{"alias_kind":"pith_short_8","alias_value":"3JH3QO7P","created_at":"2026-05-18T12:27:32Z"}],"graph_snapshots":[{"event_id":"sha256:9c78731751f065ff256c84cd97aa9cde8a4fbcafeff06b6c0162d6ad879dcacd","target":"graph","created_at":"2026-05-18T03:18:06Z","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":"An ideal source of entangled photon pairs combines the perfect symmetry of an atom with the convenient electrical trigger of light sources based on semiconductor quantum dots. We create a naturally symmetric quantum dot cascade that emits highly entangled photon pairs on demand. Our source consists of strain-free GaAs dots self-assembled on a triangular symmetric (111)A surface. The emitted photons strongly violate Bell's inequality and reveal a fidelity to the Bell state as high as 86 (+-2) % without postselection. This result is an important step towards scalable quantum-communication applic","authors_text":"B. Urbaszek, H. Kumano, H. Nakajima, I. Suemune, K. Sakoda, M. Abbarachi, M. Jo, N. Ha, T. Amand, T. Kuroda, T. Mano, X. Marie, Y. Sakuma","cross_cats":["cond-mat.mes-hall"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-02-26T10:44:15Z","title":"Symmetric quantum dots as efficient sources of highly entangled photons"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1302.6389","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":"sha256:8e5a506e1a1a337d3beb60e6949990bdb570f9a183d7da55819f93074a9ef2cb","target":"record","created_at":"2026-05-18T03:18:06Z","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":"8cce5dc4c18cf6f1ad521ee539cfe8b413536f0fa2d4b3f16ead86b0c20d84c2","cross_cats_sorted":["cond-mat.mes-hall"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2013-02-26T10:44:15Z","title_canon_sha256":"0e2fa171680062544d686f9c97048d2f9f39a26a5a35a23d6ec8eacbd52abf00"},"schema_version":"1.0","source":{"id":"1302.6389","kind":"arxiv","version":1}},"canonical_sha256":"da4fb83bef4945609c3ee9e617fff68d20ef5457e784e95dee7c318b72b435d7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"da4fb83bef4945609c3ee9e617fff68d20ef5457e784e95dee7c318b72b435d7","first_computed_at":"2026-05-18T03:18:06.091205Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:18:06.091205Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"qVpzNk9LY3kSw5auZZmbsc6SiqZDHtD2y6v5lwmFVvGHyXLBogkMgAaA69/R60357IUknHZ4TBTRv6VxIRaKBA==","signature_status":"signed_v1","signed_at":"2026-05-18T03:18:06.091719Z","signed_message":"canonical_sha256_bytes"},"source_id":"1302.6389","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:8e5a506e1a1a337d3beb60e6949990bdb570f9a183d7da55819f93074a9ef2cb","sha256:9c78731751f065ff256c84cd97aa9cde8a4fbcafeff06b6c0162d6ad879dcacd"],"state_sha256":"0755e2acde42f23c025bcc5ad3b25449f83a22bf2c4f7892561d7bbcdcd6fcdc"}