{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"b9ef4356c9caa2ca327f3842daa46fbf35f4c97ecc4ea34d89fd05219ac071f0","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["8b9193cd375011e2c1597af9a2c658adfc645084080828b1296d7c4c575ec6d7","ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b"],"salt":"a4767c5afc77d60160dcd766f15e9b9b506dea72e13d858c81a23c43703170bc","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"mechanism","assisted_by":[],"external_id":"cm.insulator-quantum-oscillations.oscillation-mechanism","kind":"phenomenon","literature_status":"open","n":"2","parents":[],"plain":"Quantum oscillations normally require a sharp boundary between filled and empty electron states, which an insulator lacks. Proposed explanations range from field effects on the insulating gap to new particles that carry no charge.","posed_since":"2015","precise":"Candidates are Landau quantization of hybridized bands with a small inverted gap, which gives magnetization oscillations at the frequency of the unhybridized Fermi surface (Knolle and Cooper 2015); emergent neutral fermions with a Fermi surface (spinons, composite excitons, Majorana Fermi sea); and in-gap impurity bands or metallic inclusions. An answer predicts the frequency, the amplitude temperature dependence including deviations from Lifshitz-Kosevich form, and which quantities oscillate (magnetization, resistivity, heat capacity, thermopower) in $\\mathrm{SmB_6}$, $\\mathrm{YbB_{12}}$ and monolayer $\\mathrm{WTe_2}$.","problem_ref":"8b9193cd375011e2c1597af9a2c658adfc645084080828b1296d7c4c575ec6d7","references":"","settled_by":"Amplitude versus temperature and gap size in a tunable system (pressure-tuned $\\mathrm{YbB_{12}}$, gate-tuned $\\mathrm{WTe_2}$ or InAs/GaSb wells) where the candidate theories make distinct predictions.","status_note":"","title":"How can an insulator without a Fermi surface show quantum oscillations?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"a362bd62b146d353f110c3268f32cc72b50277d40084e7456548a0e38d51334c","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"3c85a0b9897ffe4978fea4f3b81dd35c6ba93e852c52a639572a7d6edb30bd73","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"AtnHx-CGeeRpi3TQ9gghKgq3ryFExI8CpBxDxVJrD19rR6Rdp1QjWNySrqLVf-5KkknNDS9MPg-IK5dGsYudCA"},"schema":"pubphys.envelope/1"},"record_hash":"a362bd62b146d353f110c3268f32cc72b50277d40084e7456548a0e38d51334c","leaf_index":2868}