{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2016:YC4EHUN7ULJKGK7FDRVOP4POEZ","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":"0589a488143b8e6b6c49e49079e6f99c0e3375c30a276df98530c5d617497e9e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2016-12-29T19:43:03Z","title_canon_sha256":"0576755ffe63fb89791c0f731c1c1ea7d31de97b4ed5e971ab8f435df6092b93"},"schema_version":"1.0","source":{"id":"1612.09261","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1612.09261","created_at":"2026-05-18T00:53:46Z"},{"alias_kind":"arxiv_version","alias_value":"1612.09261v1","created_at":"2026-05-18T00:53:46Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1612.09261","created_at":"2026-05-18T00:53:46Z"},{"alias_kind":"pith_short_12","alias_value":"YC4EHUN7ULJK","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_16","alias_value":"YC4EHUN7ULJKGK7F","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_8","alias_value":"YC4EHUN7","created_at":"2026-05-18T12:30:53Z"}],"graph_snapshots":[{"event_id":"sha256:df8c647ec951dd4ce331a51a09cbf04a8658245c8f244e6096a64be5210b8d15","target":"graph","created_at":"2026-05-18T00:53:46Z","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":"Quantum communication over long distances is integral to information security and has been demonstrated in free space and fibre with two-dimensional polarisation states of light. Although increased bit rates can be achieved using high-dimensional encoding with spatial modes of light, the efficient detection of high-dimensional states remains a challenge to realise the full benefit of the increased state space. Here we exploit the entanglement between spatial modes and polarization to realise a four-dimensional quantum key distribution (QKD) protocol. We introduce a detection scheme which emplo","authors_text":"Andrew Forbes, Benjamin Perez-Garcia, Bienvenu Ndagano, Isaac Nape, Raul I. Hernandez-Aranda, Stirling Scholes, Thomas Konrad","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2016-12-29T19:43:03Z","title":"High-bit-rate quantum key distribution with entangled internal degrees of freedom of photons"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1612.09261","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":"sha256:4105a71e62e69de98549b58a2d4729b58ff3125b82c0ffa801265043355bc94a","target":"record","created_at":"2026-05-18T00:53:46Z","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":"0589a488143b8e6b6c49e49079e6f99c0e3375c30a276df98530c5d617497e9e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2016-12-29T19:43:03Z","title_canon_sha256":"0576755ffe63fb89791c0f731c1c1ea7d31de97b4ed5e971ab8f435df6092b93"},"schema_version":"1.0","source":{"id":"1612.09261","kind":"arxiv","version":1}},"canonical_sha256":"c0b843d1bfa2d2a32be51c6ae7f1ee2671c02e1f6bf03f89ad24442e6112b563","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c0b843d1bfa2d2a32be51c6ae7f1ee2671c02e1f6bf03f89ad24442e6112b563","first_computed_at":"2026-05-18T00:53:46.143380Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:53:46.143380Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"UC0Khs/kOUtAyMisgw+O1pvZEc8DPmf/hRyyPkDiNP9Ihr1BSp0dhK0ApwyBMoU1BSXvYN6VN7fHxEGA8vThCg==","signature_status":"signed_v1","signed_at":"2026-05-18T00:53:46.143843Z","signed_message":"canonical_sha256_bytes"},"source_id":"1612.09261","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4105a71e62e69de98549b58a2d4729b58ff3125b82c0ffa801265043355bc94a","sha256:df8c647ec951dd4ce331a51a09cbf04a8658245c8f244e6096a64be5210b8d15"],"state_sha256":"623eaa6df59e10551f171e3568a5abdfb12fc31f84c66198718ed8ea40e261e0"}