{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"2e731e7b3be7a7c98b25dbfc4612f20f2c2bc061c12a2c3277d13d2a091cdedb","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":["ai:gpt-5.5"],"kind":"seed"},"parents":["4b15bf14f927784843fc0baa015776b80a06c45567c265054af6a8d6344ae509","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"7bb829ff218a81cf5c8be3f3e1dd61c2e877d241dadb31db5271528d1e7b38f8","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":["ai:gpt-5.5"],"external_id":"qi.tunneling-arrival-time.attoclock-delay","kind":"well-posed","literature_status":"contested","n":"2","parents":[],"plain":"An attoclock uses a rotating laser field, like the hand of a clock, to time when an electron escapes an atom by tunneling. Experiments and analyses disagree on whether the escape takes a finite time or none.","posed_since":"2008","precise":"In elliptically polarized strong-field ionization of atomic hydrogen or helium, extract the tunneling delay $\\tau_T$ from the photoelectron momentum offset angle after subtracting the Coulomb deflection computed from the full time-dependent Schrodinger equation, and decide whether $\\tau_T = 0$ within resolution. A 2019 hydrogen experiment (Sainadh et al., Nature) reported $\\tau_{T}$ below about $1.8 \\times 10^{-18}\\,\\mathrm{s}$.","problem_ref":"4b15bf14f927784843fc0baa015776b80a06c45567c265054af6a8d6344ae509","references":"","settled_by":"Agreement between calibrated attoclock measurements on hydrogen at several intensities and a clock-model prediction.","status_note":"2025 analyses (e.g. arXiv:2503.07859) continue to compare attoclock and Larmor-clock interpretations of strong-field tunneling.","title":"Is there a nonzero tunneling delay in strong-field ionization?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"24db415518904d411c259a9f6e57eb1812170b3b96bce62ee6f256bb8bcc72b2","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"fa9d9f99717ce71035e96cb7a7dc52ba6ecffe4bfa18b2d8d9b01dd94b600591","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"0yip7u17YODTJEexnojJQiPF2wLFYe5d0Z03V8HnY0fQoqI6r10rUWBbp6PK-9cuEzr1Yyl7epvUC0A5itROCA"},"schema":"pubphys.envelope/1"},"record_hash":"24db415518904d411c259a9f6e57eb1812170b3b96bce62ee6f256bb8bcc72b2","leaf_index":3764}