{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"ec6c6bc5203f6c17c7f7b0756130127753c2b054516ff7dff20a8c312cecde2b","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["183e79026db85b21406f5df4c36a6c7d3635be9ca1f4246146875d83810df5d8","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"2990e2b66a124307d98d218844640caf3191e76b3f38934e4ae5f703b2a0fc95","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"amo.attosecond-electron-dynamics.solid-hhg-mechanism","kind":"phenomenon","literature_status":"contested","n":"2","parents":[],"plain":"An intense infrared laser shining on a crystal makes it emit light at many multiples of the laser frequency (high harmonics). Two pictures compete: electrons accelerating within one energy band, or electrons and holes recombining across the band gap.","posed_since":"2011","precise":"Bulk or monolayer crystals (ZnO, $\\mathrm{SiO_2}$, GaSe, $\\mathrm{MoS_2}$) driven by a mid-infrared field with Keldysh parameter $\\gamma < 1$ below the damage threshold. Quantity: the fraction of the harmonic yield in each order from the interband polarization (electron-hole recollision) versus the intraband current (nonparabolic band motion, Bloch-like oscillation), as a function of order, field strength and wavelength. An answer is an experimental observable that separates the two contributions unambiguously (harmonic phase, ellipticity or two-color response) in at least one material, matched by a parameter-free microscopic calculation.","problem_ref":"183e79026db85b21406f5df4c36a6c7d3635be9ca1f4246146875d83810df5d8","references":"","settled_by":"Phase-resolved harmonic measurements in a well-characterized crystal compared with ab initio time-dependent calculations that include propagation through the sample.","status_note":"Different materials and drive wavelengths have been reported to favor different dominant mechanisms; no unified microscopic account exists as of 2024.","title":"Interband versus intraband currents in high-harmonic generation from solids","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"08183ef2d7adab01c2d2d39bd5d7cd3220c2d2d8cacf7fdc46d9d81e0860c0e1","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"7596691c6517840486af6afb7b8843a55799e44562cfd3b95a7274f535affb40","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"uosKpShhDLnDLmEadmcM_IFu6hBc50-_SENi756jBSt383g8VbRpfbVOtDk_wZC7d5XnsBwlLFvNLxs7KnweAg"},"schema":"pubphys.envelope/1"},"record_hash":"08183ef2d7adab01c2d2d39bd5d7cd3220c2d2d8cacf7fdc46d9d81e0860c0e1","leaf_index":2194}