{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2009:V5HEPVJKN2WIZONGY5UQCKFTHB","short_pith_number":"pith:V5HEPVJK","canonical_record":{"source":{"id":"0910.2407","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2009-10-13T14:36:06Z","cross_cats_sorted":["cond-mat.mes-hall"],"title_canon_sha256":"00b944afca44a78c8174bb70ad70a07e3af6f15b19af04071b78014133e9e9d6","abstract_canon_sha256":"dda02168dc17e9b7b4cf892ea403e954bb5aa89f06886248b87159b927bdcac9"},"schema_version":"1.0"},"canonical_sha256":"af4e47d52a6eac8cb9a6c7690128b33878f1a8defebc138eae53be74e3a30de4","source":{"kind":"arxiv","id":"0910.2407","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0910.2407","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"arxiv_version","alias_value":"0910.2407v1","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0910.2407","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"pith_short_12","alias_value":"V5HEPVJKN2WI","created_at":"2026-05-18T12:26:02Z"},{"alias_kind":"pith_short_16","alias_value":"V5HEPVJKN2WIZONG","created_at":"2026-05-18T12:26:02Z"},{"alias_kind":"pith_short_8","alias_value":"V5HEPVJK","created_at":"2026-05-18T12:26:02Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2009:V5HEPVJKN2WIZONGY5UQCKFTHB","target":"record","payload":{"canonical_record":{"source":{"id":"0910.2407","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2009-10-13T14:36:06Z","cross_cats_sorted":["cond-mat.mes-hall"],"title_canon_sha256":"00b944afca44a78c8174bb70ad70a07e3af6f15b19af04071b78014133e9e9d6","abstract_canon_sha256":"dda02168dc17e9b7b4cf892ea403e954bb5aa89f06886248b87159b927bdcac9"},"schema_version":"1.0"},"canonical_sha256":"af4e47d52a6eac8cb9a6c7690128b33878f1a8defebc138eae53be74e3a30de4","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:11:24.119341Z","signature_b64":"aBO+7WLznCgKRvs9A1Z0veyrxCRC0mctAPZxfVnkV+ZQ6pPTVLm0eLeFnPX8l9kC3IHWdANbJMqVPu845Nm8CQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"af4e47d52a6eac8cb9a6c7690128b33878f1a8defebc138eae53be74e3a30de4","last_reissued_at":"2026-05-18T02:11:24.118515Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:11:24.118515Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0910.2407","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":"2026-05-18T02:11:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9xHPoAM5ojvbBXxf3Ao2q5Xwy7igV6E1s7CiK/dLFgaoJ9FZsxwhzEAo4kRVEXF4JPgUWGD+8enq5grISa2OAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T01:56:16.365671Z"},"content_sha256":"0d5c51324c1368fcbc01286c618dbdf494f236c02c1a051a6ea8fb583c88e849","schema_version":"1.0","event_id":"sha256:0d5c51324c1368fcbc01286c618dbdf494f236c02c1a051a6ea8fb583c88e849"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2009:V5HEPVJKN2WIZONGY5UQCKFTHB","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Symmetry-induced gap opening in graphene superlattices","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.mes-hall"],"primary_cat":"cond-mat.mtrl-sci","authors_text":"Gian Franco Tantardini, Rocco Martinazzo, Simone Casolo","submitted_at":"2009-10-13T14:36:06Z","abstract_excerpt":"We study nxn honeycomb superlattices of defects in graphene. The considered defects are missing p_z orbitals and can be realized by either introducing C atom vacancies or chemically binding simple atomic species at the given sites. Using symmetry arguments we show how it is possible to open a gap when n=3m+1,3m+2 (m integer), and estimate its value to have an approximate square-root dependence on the defect concentration x=1/n^2. Tight-binding calculations confirm these findings and show that the induced-gaps can be quite large, e.g. ~100 meV for x~10^{-3}. Gradient-corrected density functiona"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0910.2407","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":"2026-05-18T02:11:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"rNUocgoRJOZwKygl+LliDoKpcxFro6iwSs0CpHYU4AveLDrD4CILp5YyJj8iam6CAD3OiPczscmd2LxKT4qDCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T01:56:16.366026Z"},"content_sha256":"d3c0340542a1fba4ac13cb78a28850c020b3792c1428bd11694947c0614de1c4","schema_version":"1.0","event_id":"sha256:d3c0340542a1fba4ac13cb78a28850c020b3792c1428bd11694947c0614de1c4"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/bundle.json","state_url":"https://pith.science/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/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":"2026-05-31T01:56:16Z","links":{"resolver":"https://pith.science/pith/V5HEPVJKN2WIZONGY5UQCKFTHB","bundle":"https://pith.science/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/bundle.json","state":"https://pith.science/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/state.json","well_known_bundle":"https://pith.science/.well-known/pith/V5HEPVJKN2WIZONGY5UQCKFTHB/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2009:V5HEPVJKN2WIZONGY5UQCKFTHB","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":"dda02168dc17e9b7b4cf892ea403e954bb5aa89f06886248b87159b927bdcac9","cross_cats_sorted":["cond-mat.mes-hall"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2009-10-13T14:36:06Z","title_canon_sha256":"00b944afca44a78c8174bb70ad70a07e3af6f15b19af04071b78014133e9e9d6"},"schema_version":"1.0","source":{"id":"0910.2407","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0910.2407","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"arxiv_version","alias_value":"0910.2407v1","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0910.2407","created_at":"2026-05-18T02:11:24Z"},{"alias_kind":"pith_short_12","alias_value":"V5HEPVJKN2WI","created_at":"2026-05-18T12:26:02Z"},{"alias_kind":"pith_short_16","alias_value":"V5HEPVJKN2WIZONG","created_at":"2026-05-18T12:26:02Z"},{"alias_kind":"pith_short_8","alias_value":"V5HEPVJK","created_at":"2026-05-18T12:26:02Z"}],"graph_snapshots":[{"event_id":"sha256:d3c0340542a1fba4ac13cb78a28850c020b3792c1428bd11694947c0614de1c4","target":"graph","created_at":"2026-05-18T02:11:24Z","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 study nxn honeycomb superlattices of defects in graphene. The considered defects are missing p_z orbitals and can be realized by either introducing C atom vacancies or chemically binding simple atomic species at the given sites. Using symmetry arguments we show how it is possible to open a gap when n=3m+1,3m+2 (m integer), and estimate its value to have an approximate square-root dependence on the defect concentration x=1/n^2. Tight-binding calculations confirm these findings and show that the induced-gaps can be quite large, e.g. ~100 meV for x~10^{-3}. Gradient-corrected density functiona","authors_text":"Gian Franco Tantardini, Rocco Martinazzo, Simone Casolo","cross_cats":["cond-mat.mes-hall"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2009-10-13T14:36:06Z","title":"Symmetry-induced gap opening in graphene superlattices"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0910.2407","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":"sha256:0d5c51324c1368fcbc01286c618dbdf494f236c02c1a051a6ea8fb583c88e849","target":"record","created_at":"2026-05-18T02:11:24Z","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":"dda02168dc17e9b7b4cf892ea403e954bb5aa89f06886248b87159b927bdcac9","cross_cats_sorted":["cond-mat.mes-hall"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mtrl-sci","submitted_at":"2009-10-13T14:36:06Z","title_canon_sha256":"00b944afca44a78c8174bb70ad70a07e3af6f15b19af04071b78014133e9e9d6"},"schema_version":"1.0","source":{"id":"0910.2407","kind":"arxiv","version":1}},"canonical_sha256":"af4e47d52a6eac8cb9a6c7690128b33878f1a8defebc138eae53be74e3a30de4","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"af4e47d52a6eac8cb9a6c7690128b33878f1a8defebc138eae53be74e3a30de4","first_computed_at":"2026-05-18T02:11:24.118515Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:11:24.118515Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"aBO+7WLznCgKRvs9A1Z0veyrxCRC0mctAPZxfVnkV+ZQ6pPTVLm0eLeFnPX8l9kC3IHWdANbJMqVPu845Nm8CQ==","signature_status":"signed_v1","signed_at":"2026-05-18T02:11:24.119341Z","signed_message":"canonical_sha256_bytes"},"source_id":"0910.2407","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:0d5c51324c1368fcbc01286c618dbdf494f236c02c1a051a6ea8fb583c88e849","sha256:d3c0340542a1fba4ac13cb78a28850c020b3792c1428bd11694947c0614de1c4"],"state_sha256":"11dd2dcab4d31d81857c2105a02321ed65038d39b26a9b67ef81e098b88d2946"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"wosgTa4fydw/iCjTKUVLwpkxl+tTWYVAUSkaWPy6Nea5H8pDFumcIAd4miFkQVmA59djz/VVR7MSSFN2qQCIBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T01:56:16.368271Z","bundle_sha256":"798065cc6c0b6e66f0e53f200bc563081168218291a75f2af8f8b70a76667240"}}