{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:I54KFRIACQKDKKFKBIYHJZSW7D","short_pith_number":"pith:I54KFRIA","canonical_record":{"source":{"id":"2108.01206","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2021-08-02T23:23:13Z","cross_cats_sorted":["quant-ph"],"title_canon_sha256":"e3a1a31b37ab1662e973564f111d8a5ce3c5d7ac414a5f8222199306b71f903c","abstract_canon_sha256":"cb8b411f6cf863cef1b444a2390bc12ed2d5a50582dec33a3acc21cb241a0b83"},"schema_version":"1.0"},"canonical_sha256":"4778a2c50014143528aa0a3074e656f8e2d2769018d76591567592d9d630dce3","source":{"kind":"arxiv","id":"2108.01206","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2108.01206","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"arxiv_version","alias_value":"2108.01206v2","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2108.01206","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_12","alias_value":"I54KFRIACQKD","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_16","alias_value":"I54KFRIACQKDKKFK","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_8","alias_value":"I54KFRIA","created_at":"2026-07-05T04:22:38Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:I54KFRIACQKDKKFKBIYHJZSW7D","target":"record","payload":{"canonical_record":{"source":{"id":"2108.01206","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2021-08-02T23:23:13Z","cross_cats_sorted":["quant-ph"],"title_canon_sha256":"e3a1a31b37ab1662e973564f111d8a5ce3c5d7ac414a5f8222199306b71f903c","abstract_canon_sha256":"cb8b411f6cf863cef1b444a2390bc12ed2d5a50582dec33a3acc21cb241a0b83"},"schema_version":"1.0"},"canonical_sha256":"4778a2c50014143528aa0a3074e656f8e2d2769018d76591567592d9d630dce3","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T04:22:38.497717Z","signature_b64":"FkF0a3PaGjeqq5MP0MGXRMal65Qlx9hSwWaLfKFwo3232ZIkyk9bfoKLUSxmnO2xqdQG21I6EDgZp72/PUzaAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"4778a2c50014143528aa0a3074e656f8e2d2769018d76591567592d9d630dce3","last_reissued_at":"2026-07-05T04:22:38.497210Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T04:22:38.497210Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2108.01206","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":"2026-07-05T04:22:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"tma2Pkjuumx0ozMMKIbKjbqjgPDx5AKpazddR+As3I6SBIEt6Dc43jMbqTPR45L9UDmQyf1DSecJw/oHh0jlDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T08:00:55.855809Z"},"content_sha256":"2e6b5bbcf65e96029a7a0a875d612d5a80299dd2f76bfc6d6e77a414b27d0cac","schema_version":"1.0","event_id":"sha256:2e6b5bbcf65e96029a7a0a875d612d5a80299dd2f76bfc6d6e77a414b27d0cac"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:I54KFRIACQKDKKFKBIYHJZSW7D","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Coherent spin-spin coupling mediated by virtual microwave photons","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["quant-ph"],"primary_cat":"cond-mat.mes-hall","authors_text":"Amir Sammak, Giordano Scappucci, Guoji Zheng, Jurgen Dijkema, Lieven M. K. Vandersypen, Patrick Harvey-Collard","submitted_at":"2021-08-02T23:23:13Z","abstract_excerpt":"We report the coherent coupling of two electron spins at a distance via virtual microwave photons. Each spin is trapped in a silicon double quantum dot at either end of a superconducting resonator, achieving spin-photon couplings up to around $g_s/2\\pi = 40 \\ \\text{MHz}$. As the two spins are brought into resonance with each other, but detuned from the photons, an avoided crossing larger than the spin linewidths is observed with an exchange splitting around $2J/2\\pi = 20 \\ \\text{MHz}$. In addition, photon-number states are resolved from the shift $2\\chi_s/2\\pi = -13 \\ \\text{MHz}$ that they ind"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2108.01206","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2108.01206/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T04:22:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"P3JX4M0gcKPOSZRjFzTFnx4xKJFgsFuNNng09gtWLcKdODeQKhSYv6vMhyMc7NNg2H9IjYLuC6x5wUypjFvBDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T08:00:55.856203Z"},"content_sha256":"7b672b9c7dd9b965c78e087b86617c9a28ee030178a8b6da94c0ba1c2bf1b191","schema_version":"1.0","event_id":"sha256:7b672b9c7dd9b965c78e087b86617c9a28ee030178a8b6da94c0ba1c2bf1b191"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/I54KFRIACQKDKKFKBIYHJZSW7D/bundle.json","state_url":"https://pith.science/pith/I54KFRIACQKDKKFKBIYHJZSW7D/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/I54KFRIACQKDKKFKBIYHJZSW7D/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":"2026-07-07T08:00:55Z","links":{"resolver":"https://pith.science/pith/I54KFRIACQKDKKFKBIYHJZSW7D","bundle":"https://pith.science/pith/I54KFRIACQKDKKFKBIYHJZSW7D/bundle.json","state":"https://pith.science/pith/I54KFRIACQKDKKFKBIYHJZSW7D/state.json","well_known_bundle":"https://pith.science/.well-known/pith/I54KFRIACQKDKKFKBIYHJZSW7D/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:I54KFRIACQKDKKFKBIYHJZSW7D","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":"cb8b411f6cf863cef1b444a2390bc12ed2d5a50582dec33a3acc21cb241a0b83","cross_cats_sorted":["quant-ph"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2021-08-02T23:23:13Z","title_canon_sha256":"e3a1a31b37ab1662e973564f111d8a5ce3c5d7ac414a5f8222199306b71f903c"},"schema_version":"1.0","source":{"id":"2108.01206","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2108.01206","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"arxiv_version","alias_value":"2108.01206v2","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2108.01206","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_12","alias_value":"I54KFRIACQKD","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_16","alias_value":"I54KFRIACQKDKKFK","created_at":"2026-07-05T04:22:38Z"},{"alias_kind":"pith_short_8","alias_value":"I54KFRIA","created_at":"2026-07-05T04:22:38Z"}],"graph_snapshots":[{"event_id":"sha256:7b672b9c7dd9b965c78e087b86617c9a28ee030178a8b6da94c0ba1c2bf1b191","target":"graph","created_at":"2026-07-05T04:22:38Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2108.01206/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We report the coherent coupling of two electron spins at a distance via virtual microwave photons. Each spin is trapped in a silicon double quantum dot at either end of a superconducting resonator, achieving spin-photon couplings up to around $g_s/2\\pi = 40 \\ \\text{MHz}$. As the two spins are brought into resonance with each other, but detuned from the photons, an avoided crossing larger than the spin linewidths is observed with an exchange splitting around $2J/2\\pi = 20 \\ \\text{MHz}$. In addition, photon-number states are resolved from the shift $2\\chi_s/2\\pi = -13 \\ \\text{MHz}$ that they ind","authors_text":"Amir Sammak, Giordano Scappucci, Guoji Zheng, Jurgen Dijkema, Lieven M. K. Vandersypen, Patrick Harvey-Collard","cross_cats":["quant-ph"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2021-08-02T23:23:13Z","title":"Coherent spin-spin coupling mediated by virtual microwave photons"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2108.01206","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":"sha256:2e6b5bbcf65e96029a7a0a875d612d5a80299dd2f76bfc6d6e77a414b27d0cac","target":"record","created_at":"2026-07-05T04:22:38Z","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":"cb8b411f6cf863cef1b444a2390bc12ed2d5a50582dec33a3acc21cb241a0b83","cross_cats_sorted":["quant-ph"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2021-08-02T23:23:13Z","title_canon_sha256":"e3a1a31b37ab1662e973564f111d8a5ce3c5d7ac414a5f8222199306b71f903c"},"schema_version":"1.0","source":{"id":"2108.01206","kind":"arxiv","version":2}},"canonical_sha256":"4778a2c50014143528aa0a3074e656f8e2d2769018d76591567592d9d630dce3","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"4778a2c50014143528aa0a3074e656f8e2d2769018d76591567592d9d630dce3","first_computed_at":"2026-07-05T04:22:38.497210Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T04:22:38.497210Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"FkF0a3PaGjeqq5MP0MGXRMal65Qlx9hSwWaLfKFwo3232ZIkyk9bfoKLUSxmnO2xqdQG21I6EDgZp72/PUzaAA==","signature_status":"signed_v1","signed_at":"2026-07-05T04:22:38.497717Z","signed_message":"canonical_sha256_bytes"},"source_id":"2108.01206","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2e6b5bbcf65e96029a7a0a875d612d5a80299dd2f76bfc6d6e77a414b27d0cac","sha256:7b672b9c7dd9b965c78e087b86617c9a28ee030178a8b6da94c0ba1c2bf1b191"],"state_sha256":"a250f1dac6f8112be0e6a896135f14d8bade9904cf2124f5e2a09e03f9fe7a1a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"DhvC+al3KJ9aNuGUy0TFeeG+Y/2EkO9sfjS4AFuKMmgZgkwqP2Kub1a5KGq1be6VE9K7U90ZhCNolfuyJx7ADA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-07T08:00:55.858207Z","bundle_sha256":"d487769e494d40dca89ef5b8b7960786b040322593fb174ea00be736b58654a0"}}