Pressure-quench protocols can stabilise pressure-induced or pressure-enhanced superconducting states at ambient pressure.
Evidence is materially increasing confidence in—or pressure on—the claim; significant uncertainty remains. State definitions
No evidence has been admitted since this assessment.
Retained questions may have been narrowed or reframed by the current assessment.
Verification position derived from the record’s assessments; dates show when Faultline first recorded each stage.
FCIF Admission Review is the Observatory’s process for deciding whether a claim enters the record; it is not external scientific peer review. Normal Record Review is the Observatory’s assessment process for newly considered evidence, not external scientific peer review. LPR identifies an internal source-review record. PROG identifies a programme: AI (Artificial Intelligence), AM (Advanced Materials), BT (Biotechnology), or QE (Quantum Engineering).
How the claim could hold, what obstructs it, and possible ways forward. The State Warrant above remains the authoritative current assessment.
Thermal metastability. Pressure quenching can remove the external pressure requirement while leaving the retained superconducting phase dependent on thermal history. In Hg1223, the enhanced state degrades when warmed and can lose much of its transition-temperature enhancement after excursions above roughly 200 K. This is a structural limitation: ambient pressure alone does not establish that the quenched phase can be stored, handled, or cycled under ordinary ambient-temperature conditions.
Originating-group concentration. The cross-material evidence is stronger than a one-off observation, but the principal demonstrations are concentrated within one research programme and its collaborators. Until an unaffiliated laboratory reproduces pressure-quench retention using a published protocol, programme-specific technique, apparatus, sample preparation, or interpretation remain viable alternative explanations for the apparent generality.
Protocol and history dependence. The retained state depends on pressure magnitude, quench temperature, decompression path, defects, stoichiometry, and potentially oxygen or vacancy rearrangement. Strong path dependence can make a phenomenon physically real while still preventing reproducible transfer between laboratories or material batches. The claim therefore requires protocol-level reproducibility, not merely repeated positive samples within one experimental lineage.
Scale and recovery gap. Current demonstrations rely on very small samples processed under diamond-anvil-cell or comparable extreme-pressure conditions. Retaining a superconducting state after decompression does not yet show that useful quantities of material can be produced, recovered, processed, or incorporated into devices without erasing the metastable phase.
A recorded possible resolution path, not automatically a sufficient test for closing the claim.
Independent pressure-quench replication. An unaffiliated laboratory reproduces retention of a pressure-induced or pressure-enhanced superconducting state at ambient pressure using a published pressure-quench protocol and independent material preparation. This would remove the largest current verification bottleneck and justify movement beyond VS-03.
A recorded possible resolution path, not automatically a sufficient test for closing the claim.
Thermally durable retained high-Tc state. A pressure-enhanced superconducting state remains stable at ambient pressure through room-temperature handling and subsequent cooling cycles while preserving materially enhanced superconducting properties. This would distinguish pressure removal from genuinely usable ambient-condition retention and would materially change the technological significance of the claim.
Historical narrative recorded for this claim. It does not override the current State Warrant.
Questions retained in this record. The current State Warrant may have narrowed or reframed them. Recorded dates refer to question history, not necessarily the age of the current wording; known revision dates are shown separately.
Is pressure quenching a broadly general method for trapping metastable superconducting states, or does successful retention depend on a narrow subset of materials with favourable structural or electronic transitions?
Question recorded 2026-08-25What physically stabilises the retained state after decompression — defects, strain, oxygen or vacancy rearrangement, electronic reconstruction, or a combination of mechanisms — and can that mechanism predict which materials should be quenchable?
Question recorded 2026-08-25Can a pressure-quenched high-Tc state survive room-temperature storage and handling and then recover the same enhanced superconducting properties on subsequent cooling?
Question recorded 2026-08-25Can pressure-quench retention be reproduced by an unaffiliated laboratory from a published protocol without tacit knowledge from the originating research programme?
Question recorded 2026-08-25| Mutation | Date | Field | Prior value | Current value |
|---|---|---|---|---|
| M-009 | 2026-10-19 | Reference correctionreference_corrected | IN-001 / IN-002 shared FeSe publication implicit in sources | IN-002 explicitly linked to IN-001 as partial publication overlapWhat this update recorded for M-009Both entries cite Deng et al. (2021), DOI 10.1073/pnas.2108938118. IN-001 also cites Wu et al. (2020) on antimony. Make the partial overlap explicit without merging distinct evidence or claiming independent replication. Preserve all assessments, descriptions, sources, dates and vectors; no new evidence admitted. |
| M-008 | 2026-10-16 | Source reviewprovenance_review | LPR-001-D24 | LPR-001-D52What this update recorded for M-008Second-cycle Legacy Provenance Review completed as PASS across all four existing evidence instances. Underlying sources and claim representation verified; existing structured provenance is sufficient and no unverifiable attribution was introduced. No factual, interpretive, attribution, or verification-stage discrepancy identified. No genuinely new scientific evidence admitted or flagged for Normal Record Review. Canonical outcome verified / not_required; Pressure State and Verification Stage unchanged. |
| M-007 | 2026-09-22 | Source or history correctionprovenance_correction | LPR-001-D24 discrepancies_found / pending | LPR-001-D24 discrepancies_corrected / completedWhat this update recorded for M-007Approved bounded correction of IN-002. Replaced the unsupported 2022–24 subsequent-extension chronology with the source-faithful 2021 same-study FeSe/Cu-doped-FeSe comparison; added the primary PNAS provenance; and aligned the dependent 2022–24 lineage wording. Consistency review confirms AS-001, ESCALATING / VS-03, mechanisms, attractors, and open questions remain valid because the record's cross-material trajectory is independently carried by Sb, Bi0.5Sb1.5Te3, and Hg1223 evidence. No new evidence admitted. |
| M-006 | 2026-09-22 | Source reviewprovenance_review | — | LPR-001-D24 REVIEW REQUIREDWhat this update recorded for M-006Legacy provenance review completed. IN-001, IN-003 and IN-004 were verified against the named peer-reviewed primary papers and received structured sources[]. IN-002 requires bounded correction before provenance can be attached: its characterisation of Cu-doped FeSe as a subsequent 2022–24 cross-material extension is chronologically inaccurate, because Cu-doped FeSe is reported alongside pure FeSe in the 2021 PNAS pressure-quench paper. The core pressure-quench trajectory and the current AS-001 state are not silently changed. No new evidence admitted through LPR-001. |
| M-005 | 2026-08-25 | Assessment issuedassessment_issued | — | AS-001What this update recorded for M-005Initial governed assessment logged for the admission decision: ESCALATING / VS-03. This mutation records the already-issued AS-001 and does not change its substance, pressure state, or verification stage. |
| M-004 | 2026-08-25 | Opened date addedopened_date_added | — | 2026-08-25What this update recorded for M-004Canonical openedDate added as the actual FCIF admission date. The field remains operationally required for Record Directory sorting even though opened-date display was removed from the public UI. No evidentiary or assessment change. |
| M-003 | 2026-08-25 | Related records correctedrelated_records_corrected | bare record identifiers | governed related-record objectsWhat this update recorded for M-003Schema-shape correction after prerender validation exposed that relatedRecords requires id, relationship, and note fields. FR-AM-0003 and FR-AM-0005 relationships are preserved; no claim, evidence, assessment, pressure state, or verification stage changed. |
| M-002 | 2026-08-25 | Instances loggedinstances_logged | — | IN-001–IN-004What this update recorded for M-002Initial evidence trail logged at admission following the bounded FCIF Admission Review: IN-001 through IN-004 reconstruct the pressure-quench superconductivity trajectory from the early Sb/FeSe demonstrations through the March 2026 Hg1223 result. |
| M-001 | 2026-08-25 | Record createdrecord_created | — | RECORD-CREATEDWhat this update recorded for M-001FR-AM-0007 admitted following bounded FCIF Admission Review. Initial state ESCALATING; verification stage VS-03. Scope limited to retention of pressure-induced or pressure-enhanced superconducting states at ambient pressure. |
Logged entries are reports on record, not counts of independent studies or patients. Several entries can concern the same underlying evidence. Supportive and Contesting describe an entry’s relation to the claim. Partial indicates limited or mixed bearing; read the details for limitations or legacy status. These labels are not study-quality ratings.
Shares the FeSe paper (Deng et al., 2021) with IN-002. This entry also includes separate antimony evidence; the entries partly overlap and are not independent replications. View IN-002
A sequence of experiments led by the University of Houston programme reports that superconducting states created or enhanced under high pressure can persist after pressure is released when decompression is performed under controlled low-temperature conditions. Early demonstrations in Sb and FeSe establish the core pressure-quench proposition: the superconducting state need not vanish immediately when the pressure that created or enhanced it is removed. These originating results are supportive but remain concentrated within one research programme and do not by themselves establish broad material generality.
Shares the FeSe paper (Deng et al., 2021) with IN-001. This entry isolates its composition comparison; IN-001 also includes separate antimony evidence. Partial source overlap, not an independent replication. View IN-001
The 2021 PNAS pressure-quench study reports retention at ambient pressure in both pure FeSe and Cu-doped FeSe. The Cu-doped result supplies a composition-level comparison within the FeSe material family; it is not a later 2022–24 extension or evidence of a separate material family. It modestly weakens a single-specimen interpretation, but the evidence remains concentrated within the originating research programme and does not constitute independent institutional replication.
A peer-reviewed PNAS study reports that a pressure-induced superconducting state in Bi0.5Sb1.5Te3 can be retained at ambient pressure using pressure quenching, including recovery of the quenched material from the diamond-anvil-cell environment while preserving the metastable state. This materially strengthens the claim because the method is demonstrated in another material family and because retention survives physical recovery from the pressure apparatus. The result remains subject to the same institutional-concentration limitation: it extends the protocol's material range but does not yet provide unaffiliated replication.
A March 2026 PNAS study applies pressure quenching to HgBa2Ca2Cu3O8+δ (Hg1223), whose ordinary ambient-pressure superconducting transition is approximately 133 K. Across multiple samples, the researchers report retained ambient-pressure transition temperatures of approximately 147–151 K after preparation at high pressure, establishing a new ambient-pressure superconducting temperature record. Resistance, magnetic, synchrotron X-ray, and supporting calculations are used to characterise the retained state. The result is strongly supportive of the admitted claim because the pressure-enhanced superconducting state persists after decompression. It does not establish technological ambient-condition usability: the retained state is metastable, degrades with warming, and can lose much of the enhancement after thermal cycling above roughly 200 K.