{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:LRGAIB6Q2D5VDC4J4CSTFEJQ2C","short_pith_number":"pith:LRGAIB6Q","canonical_record":{"source":{"id":"1901.08851","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.app-ph","submitted_at":"2019-01-25T12:30:55Z","cross_cats_sorted":["cond-mat.mes-hall","physics.optics"],"title_canon_sha256":"503f36df24fcc2f811ac3979cd34753d0a3c3b0a95006685762c536e8455f400","abstract_canon_sha256":"e663f77ac3ecba72faba6dab01dde4574fd0ffc54978d59938026fef45e23b4e"},"schema_version":"1.0"},"canonical_sha256":"5c4c0407d0d0fb518b89e0a5329130d0a98a4192ec911a12f222b1ae40f81b79","source":{"kind":"arxiv","id":"1901.08851","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.08851","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"arxiv_version","alias_value":"1901.08851v1","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.08851","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"pith_short_12","alias_value":"LRGAIB6Q2D5V","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"LRGAIB6Q2D5VDC4J","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"LRGAIB6Q","created_at":"2026-05-18T12:33:21Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:LRGAIB6Q2D5VDC4J4CSTFEJQ2C","target":"record","payload":{"canonical_record":{"source":{"id":"1901.08851","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.app-ph","submitted_at":"2019-01-25T12:30:55Z","cross_cats_sorted":["cond-mat.mes-hall","physics.optics"],"title_canon_sha256":"503f36df24fcc2f811ac3979cd34753d0a3c3b0a95006685762c536e8455f400","abstract_canon_sha256":"e663f77ac3ecba72faba6dab01dde4574fd0ffc54978d59938026fef45e23b4e"},"schema_version":"1.0"},"canonical_sha256":"5c4c0407d0d0fb518b89e0a5329130d0a98a4192ec911a12f222b1ae40f81b79","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:55:32.909838Z","signature_b64":"QbudeTsTg4Pn6BJOamAQbDD7BCCSXOG2VbadgYFDVGtBKhPmTtd+csQFVo7iifWnpb5m9nnUAe/rnG9FgcAoAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5c4c0407d0d0fb518b89e0a5329130d0a98a4192ec911a12f222b1ae40f81b79","last_reissued_at":"2026-05-17T23:55:32.909248Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:55:32.909248Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1901.08851","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":"2026-05-17T23:55:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9BRSkE8hp9ST00taxQo7BQbN8hAIQN+K6NC6mOT62vXawWZx9WNeQY74pX1Mi+gBMfEwLqSW6NV4DFKT5RGXAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T03:00:32.258630Z"},"content_sha256":"c0c7c6bb328c49dfa363f5954a0e27b7ad75bfe056f324955ee5d70b93dcd4bb","schema_version":"1.0","event_id":"sha256:c0c7c6bb328c49dfa363f5954a0e27b7ad75bfe056f324955ee5d70b93dcd4bb"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:LRGAIB6Q2D5VDC4J4CSTFEJQ2C","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"High dynamic range, heterogeneous, terahertz quantum cascade lasers featuring thermally-tunable frequency comb operation over a broad current range","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.mes-hall","physics.optics"],"primary_cat":"physics.app-ph","authors_text":"A. Giles Davies, Edmund H. Linfield, Francesco P. Mezzapesa, Katia Garrasi, Lianhe Li, Luca Salemi, Luigi Consolino, Miriam S. Vitiello, Paolo De Natale, Saverio Bartalini","submitted_at":"2019-01-25T12:30:55Z","abstract_excerpt":"We report on the engineering of broadband quantum cascade lasers (QCLs) emitting at Terahertz (THz) frequencies, which exploit a heterogeneous active region scheme and have a current density dynamic range (Jdr) of 3.2, significantly larger than the state of the art, over a 1.3 THz bandwidth. We demonstrate that the devised broadband lasers operate as THz optical frequency comb synthesizers in continuous wave, with a maximum optical output power of 4 mW (0.73 mW in the comb regime). Measurement of the intermode beatnote map reveals a clear dispersion-compensated frequency comb regime extending "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.08851","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":"2026-05-17T23:55:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MKZL/lXulwNu1syMAr/p8KNi1nlA5ETt1YWBg5wyiET1dYd4ZQsmYRpxaF7YTsKlBwe3yvmIPLgMirRD865vAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T03:00:32.258997Z"},"content_sha256":"c0e7ea272d775b789ed52f2ae8e87df6ed165dc6bde0cbb25c08a4f1d8f73f80","schema_version":"1.0","event_id":"sha256:c0e7ea272d775b789ed52f2ae8e87df6ed165dc6bde0cbb25c08a4f1d8f73f80"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/bundle.json","state_url":"https://pith.science/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/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":"2026-05-28T03:00:32Z","links":{"resolver":"https://pith.science/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C","bundle":"https://pith.science/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/bundle.json","state":"https://pith.science/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/state.json","well_known_bundle":"https://pith.science/.well-known/pith/LRGAIB6Q2D5VDC4J4CSTFEJQ2C/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:LRGAIB6Q2D5VDC4J4CSTFEJQ2C","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":"e663f77ac3ecba72faba6dab01dde4574fd0ffc54978d59938026fef45e23b4e","cross_cats_sorted":["cond-mat.mes-hall","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.app-ph","submitted_at":"2019-01-25T12:30:55Z","title_canon_sha256":"503f36df24fcc2f811ac3979cd34753d0a3c3b0a95006685762c536e8455f400"},"schema_version":"1.0","source":{"id":"1901.08851","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.08851","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"arxiv_version","alias_value":"1901.08851v1","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.08851","created_at":"2026-05-17T23:55:32Z"},{"alias_kind":"pith_short_12","alias_value":"LRGAIB6Q2D5V","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"LRGAIB6Q2D5VDC4J","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"LRGAIB6Q","created_at":"2026-05-18T12:33:21Z"}],"graph_snapshots":[{"event_id":"sha256:c0e7ea272d775b789ed52f2ae8e87df6ed165dc6bde0cbb25c08a4f1d8f73f80","target":"graph","created_at":"2026-05-17T23:55:32Z","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 report on the engineering of broadband quantum cascade lasers (QCLs) emitting at Terahertz (THz) frequencies, which exploit a heterogeneous active region scheme and have a current density dynamic range (Jdr) of 3.2, significantly larger than the state of the art, over a 1.3 THz bandwidth. We demonstrate that the devised broadband lasers operate as THz optical frequency comb synthesizers in continuous wave, with a maximum optical output power of 4 mW (0.73 mW in the comb regime). Measurement of the intermode beatnote map reveals a clear dispersion-compensated frequency comb regime extending ","authors_text":"A. Giles Davies, Edmund H. Linfield, Francesco P. Mezzapesa, Katia Garrasi, Lianhe Li, Luca Salemi, Luigi Consolino, Miriam S. Vitiello, Paolo De Natale, Saverio Bartalini","cross_cats":["cond-mat.mes-hall","physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.app-ph","submitted_at":"2019-01-25T12:30:55Z","title":"High dynamic range, heterogeneous, terahertz quantum cascade lasers featuring thermally-tunable frequency comb operation over a broad current range"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.08851","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:c0c7c6bb328c49dfa363f5954a0e27b7ad75bfe056f324955ee5d70b93dcd4bb","target":"record","created_at":"2026-05-17T23:55:32Z","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":"e663f77ac3ecba72faba6dab01dde4574fd0ffc54978d59938026fef45e23b4e","cross_cats_sorted":["cond-mat.mes-hall","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.app-ph","submitted_at":"2019-01-25T12:30:55Z","title_canon_sha256":"503f36df24fcc2f811ac3979cd34753d0a3c3b0a95006685762c536e8455f400"},"schema_version":"1.0","source":{"id":"1901.08851","kind":"arxiv","version":1}},"canonical_sha256":"5c4c0407d0d0fb518b89e0a5329130d0a98a4192ec911a12f222b1ae40f81b79","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5c4c0407d0d0fb518b89e0a5329130d0a98a4192ec911a12f222b1ae40f81b79","first_computed_at":"2026-05-17T23:55:32.909248Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:55:32.909248Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"QbudeTsTg4Pn6BJOamAQbDD7BCCSXOG2VbadgYFDVGtBKhPmTtd+csQFVo7iifWnpb5m9nnUAe/rnG9FgcAoAA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:55:32.909838Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.08851","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:c0c7c6bb328c49dfa363f5954a0e27b7ad75bfe056f324955ee5d70b93dcd4bb","sha256:c0e7ea272d775b789ed52f2ae8e87df6ed165dc6bde0cbb25c08a4f1d8f73f80"],"state_sha256":"3d7bce39627d5a92018c17730db7c63d7650748735e18a323de0fa2e04bfd936"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8cf8XpxkdHUYRg2ySe+OR9DzGeuzXCld7/9BFuVjbdGijhU7cR+GWHJY6cxJf2IaI5Z59SKXrlFNz6z0l/ExCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T03:00:32.261092Z","bundle_sha256":"ce781bd9f9abeb6312847ca35583b2fd5eaa7c0548b857f81c2f96218b0e77de"}}