{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:YENM6EJQJYWKNBMNINBVNENXQA","short_pith_number":"pith:YENM6EJQ","canonical_record":{"source":{"id":"1907.08421","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2019-07-19T09:24:23Z","cross_cats_sorted":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"title_canon_sha256":"e46082055b7d1a0082aafedb95662ebd078abe8f183efa1882801fc53a9bac53","abstract_canon_sha256":"e4fc34d7033bb9e46d340d3e4830c2c7731c4d7684050565fdbdc8a7d78e65d3"},"schema_version":"1.0"},"canonical_sha256":"c11acf11304e2ca6858d43435691b78028ede212d3dc445c5abdfd50f259ca67","source":{"kind":"arxiv","id":"1907.08421","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1907.08421","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"arxiv_version","alias_value":"1907.08421v2","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1907.08421","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_12","alias_value":"YENM6EJQJYWK","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_16","alias_value":"YENM6EJQJYWKNBMN","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_8","alias_value":"YENM6EJQ","created_at":"2026-07-05T00:20:17Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:YENM6EJQJYWKNBMNINBVNENXQA","target":"record","payload":{"canonical_record":{"source":{"id":"1907.08421","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2019-07-19T09:24:23Z","cross_cats_sorted":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"title_canon_sha256":"e46082055b7d1a0082aafedb95662ebd078abe8f183efa1882801fc53a9bac53","abstract_canon_sha256":"e4fc34d7033bb9e46d340d3e4830c2c7731c4d7684050565fdbdc8a7d78e65d3"},"schema_version":"1.0"},"canonical_sha256":"c11acf11304e2ca6858d43435691b78028ede212d3dc445c5abdfd50f259ca67","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T00:20:17.455008Z","signature_b64":"4PKXOHOdngoABUxoUgWe2CJBe8zZzpXEUHDkgI/6S9xZsJWgVfmslDKAo2dSEZuLFPHTwriiraP1OMqG3JYTDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c11acf11304e2ca6858d43435691b78028ede212d3dc445c5abdfd50f259ca67","last_reissued_at":"2026-07-05T00:20:17.454571Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T00:20:17.454571Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1907.08421","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":"2026-07-05T00:20:17Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"6nawE6ZJOGY/SOr1QRQgJsDlXLwcgOSQu8sQtrHIwyhhPK2t5jC7hGECSrGjjhQfHJP/Sa8mR+vzA8u34UCrDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-18T10:35:17.349659Z"},"content_sha256":"674cb85c3b5f1011d36bdbe80b9d8d6f6aa8ad9390ac67e3d6245bc178346b7c","schema_version":"1.0","event_id":"sha256:674cb85c3b5f1011d36bdbe80b9d8d6f6aa8ad9390ac67e3d6245bc178346b7c"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:YENM6EJQJYWKNBMNINBVNENXQA","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Broadband Nonreciprocal Amplification in Luminal Metamaterials","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"primary_cat":"cond-mat.mes-hall","authors_text":"E. Galiffi, J. B. Pendry, P. A. Huidobro","submitted_at":"2019-07-19T09:24:23Z","abstract_excerpt":"Time has emerged as a new degree of freedom for metamaterials, promising new pathways in wave control. However, electromagnetism suffers from limitations in the modulation speed of material parameters. Here we argue that these limitations can be circumvented by introducing a traveling-wave refractive index modulation, with the same phase velocity of the waves. We show how the concept of \"luminal grating\" can yield giant nonreciprocity, achieve efficient one-way amplification, pulse compression and frequency up-conversion, proposing a realistic implementation in double-layer graphene."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1907.08421","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/1907.08421/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":"2026-07-05T00:20:17Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8S3gu5UdOLUvvztXE5mNGS3Mtogj6LD4r2rQOYAeQH6yoXHtpROMT1pUY+LjGEnW4d9mie7LbuFweDl0YuLWCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-18T10:35:17.350248Z"},"content_sha256":"16335f8f939d1e8bc4169857977422ab61e647300b53b06295bc4bfc8a626f53","schema_version":"1.0","event_id":"sha256:16335f8f939d1e8bc4169857977422ab61e647300b53b06295bc4bfc8a626f53"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/YENM6EJQJYWKNBMNINBVNENXQA/bundle.json","state_url":"https://pith.science/pith/YENM6EJQJYWKNBMNINBVNENXQA/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/YENM6EJQJYWKNBMNINBVNENXQA/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":"2026-08-18T10:35:17Z","links":{"resolver":"https://pith.science/pith/YENM6EJQJYWKNBMNINBVNENXQA","bundle":"https://pith.science/pith/YENM6EJQJYWKNBMNINBVNENXQA/bundle.json","state":"https://pith.science/pith/YENM6EJQJYWKNBMNINBVNENXQA/state.json","well_known_bundle":"https://pith.science/.well-known/pith/YENM6EJQJYWKNBMNINBVNENXQA/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:YENM6EJQJYWKNBMNINBVNENXQA","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":"e4fc34d7033bb9e46d340d3e4830c2c7731c4d7684050565fdbdc8a7d78e65d3","cross_cats_sorted":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2019-07-19T09:24:23Z","title_canon_sha256":"e46082055b7d1a0082aafedb95662ebd078abe8f183efa1882801fc53a9bac53"},"schema_version":"1.0","source":{"id":"1907.08421","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1907.08421","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"arxiv_version","alias_value":"1907.08421v2","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1907.08421","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_12","alias_value":"YENM6EJQJYWK","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_16","alias_value":"YENM6EJQJYWKNBMN","created_at":"2026-07-05T00:20:17Z"},{"alias_kind":"pith_short_8","alias_value":"YENM6EJQ","created_at":"2026-07-05T00:20:17Z"}],"graph_snapshots":[{"event_id":"sha256:16335f8f939d1e8bc4169857977422ab61e647300b53b06295bc4bfc8a626f53","target":"graph","created_at":"2026-07-05T00:20:17Z","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/1907.08421/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Time has emerged as a new degree of freedom for metamaterials, promising new pathways in wave control. However, electromagnetism suffers from limitations in the modulation speed of material parameters. Here we argue that these limitations can be circumvented by introducing a traveling-wave refractive index modulation, with the same phase velocity of the waves. We show how the concept of \"luminal grating\" can yield giant nonreciprocity, achieve efficient one-way amplification, pulse compression and frequency up-conversion, proposing a realistic implementation in double-layer graphene.","authors_text":"E. Galiffi, J. B. Pendry, P. A. Huidobro","cross_cats":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2019-07-19T09:24:23Z","title":"Broadband Nonreciprocal Amplification in Luminal Metamaterials"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1907.08421","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":"sha256:674cb85c3b5f1011d36bdbe80b9d8d6f6aa8ad9390ac67e3d6245bc178346b7c","target":"record","created_at":"2026-07-05T00:20:17Z","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":"e4fc34d7033bb9e46d340d3e4830c2c7731c4d7684050565fdbdc8a7d78e65d3","cross_cats_sorted":["cond-mat.mtrl-sci","physics.app-ph","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cond-mat.mes-hall","submitted_at":"2019-07-19T09:24:23Z","title_canon_sha256":"e46082055b7d1a0082aafedb95662ebd078abe8f183efa1882801fc53a9bac53"},"schema_version":"1.0","source":{"id":"1907.08421","kind":"arxiv","version":2}},"canonical_sha256":"c11acf11304e2ca6858d43435691b78028ede212d3dc445c5abdfd50f259ca67","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c11acf11304e2ca6858d43435691b78028ede212d3dc445c5abdfd50f259ca67","first_computed_at":"2026-07-05T00:20:17.454571Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:20:17.454571Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4PKXOHOdngoABUxoUgWe2CJBe8zZzpXEUHDkgI/6S9xZsJWgVfmslDKAo2dSEZuLFPHTwriiraP1OMqG3JYTDg==","signature_status":"signed_v1","signed_at":"2026-07-05T00:20:17.455008Z","signed_message":"canonical_sha256_bytes"},"source_id":"1907.08421","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:674cb85c3b5f1011d36bdbe80b9d8d6f6aa8ad9390ac67e3d6245bc178346b7c","sha256:16335f8f939d1e8bc4169857977422ab61e647300b53b06295bc4bfc8a626f53"],"state_sha256":"1faec73ed73fce9dfb0c548fa5f18310547c1cae619972553783073dbd7a98d4"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9j63B9twUGQ+Nqe6ljSuBl73j+W0hUukWJCc7sxIMvSR5xSHUte7d6WVfj7z75+jFFWFozloyEKfbugSRfmDAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-18T10:35:17.356515Z","bundle_sha256":"c64f9aad5afc7a5ad4afa73097a83d573cc94dfff221f82e70bb8a00e7c69c37"}}