{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:NR3R6IK7QMW6YGL2WDMRTKDBMZ","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":"fb1c143ce1ae024796d67ce6b7b9a3c34b89242a778e1bf94767ba39da9d0b3d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2026-06-16T12:16:40Z","title_canon_sha256":"754ca0c115fb682b92e777b2af81ef5e1a66d1d66ee9e699ae95c9cefab501e7"},"schema_version":"1.0","source":{"id":"2606.17848","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.17848","created_at":"2026-06-19T16:10:41Z"},{"alias_kind":"arxiv_version","alias_value":"2606.17848v1","created_at":"2026-06-19T16:10:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.17848","created_at":"2026-06-19T16:10:41Z"},{"alias_kind":"pith_short_12","alias_value":"NR3R6IK7QMW6","created_at":"2026-06-19T16:10:41Z"},{"alias_kind":"pith_short_16","alias_value":"NR3R6IK7QMW6YGL2","created_at":"2026-06-19T16:10:41Z"},{"alias_kind":"pith_short_8","alias_value":"NR3R6IK7","created_at":"2026-06-19T16:10:41Z"}],"graph_snapshots":[{"event_id":"sha256:5f878f64e1cb2b00004d0e2548034fab32cf3beb244b5c200a4e4b3039932200","target":"graph","created_at":"2026-06-19T16:10:41Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2606.17848/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Altermagnetism as a new concept in condensed matter physics is currently being thoroughly investigated. Despite the absence of macroscopic magnetization, altermagnets host a hidden spin order whose direct detection remains a challenge. Here we report on the observation of electric and magnetic dipole forbidden optical second-harmonic generation (SHG) in the altermagnet CoF$_2$ with a centrosymmetric lattice and spin order. We demonstrate that below the N\\'eel temperature $T_N = 38$ K the SHG signal is sensitive to the ferrotype magnetic octupole $\\mathbf{\\mathcal{O}}^M$ which is the order para","authors_text":"P. A. Usachev, R. V. Pisarev, V. V. Pavlov","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2026-06-16T12:16:40Z","title":"Nonlinear Optical Probing of Ferroic-Octupolar Order Parameter in Collinear Altermagnet"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.17848","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":"sha256:56152086e4cc460742e36cd090af69ae4fc9bf3cc360df28698f88a135882523","target":"record","created_at":"2026-06-19T16:10:41Z","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":"fb1c143ce1ae024796d67ce6b7b9a3c34b89242a778e1bf94767ba39da9d0b3d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.str-el","submitted_at":"2026-06-16T12:16:40Z","title_canon_sha256":"754ca0c115fb682b92e777b2af81ef5e1a66d1d66ee9e699ae95c9cefab501e7"},"schema_version":"1.0","source":{"id":"2606.17848","kind":"arxiv","version":1}},"canonical_sha256":"6c771f215f832dec197ab0d919a861666cae2c4cbf0c107cb45009a75f07c986","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6c771f215f832dec197ab0d919a861666cae2c4cbf0c107cb45009a75f07c986","first_computed_at":"2026-06-19T16:10:41.408348Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-19T16:10:41.408348Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"V+BiKjhLjZVhceVHevlkCYeph/+oCWDiUyiuSYyKersiCjjqZ54t6EtHUuLef7BvoDnMdG+wnz3fENcEFwotAQ==","signature_status":"signed_v1","signed_at":"2026-06-19T16:10:41.408837Z","signed_message":"canonical_sha256_bytes"},"source_id":"2606.17848","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:56152086e4cc460742e36cd090af69ae4fc9bf3cc360df28698f88a135882523","sha256:5f878f64e1cb2b00004d0e2548034fab32cf3beb244b5c200a4e4b3039932200"],"state_sha256":"1bbd52dfa669fd9136de94498a6df440de0275e7b91da84072b1819462d85ac5"}