Goal: Discover novel layered ternary compounds with superconducting Tc significantly above the current 2D SC ceiling (NbSe₂ ≈ 5 K monolayer), targeting Tc ≥ 15 K at ambient pressure — the threshold for practical device integration with TMD semiconductors (WS₂, MoS₂) via CVD-compatible synthesis.
Why this matters: No known 2D superconductor exceeds ~6 K. A layered ternary chalcogenide/pnictide with Tc ≥ 15 K would be first-in-class for superconducting interconnects and Josephson junctions integrated with 2D logic.
Stage | Tool | Description | Deliverable |
|---|---|---|---|
1. Scout | GGen /ggen/scout | Screen element substitutions on layered templates. Max candidates per system: ≤ 50 (route limit parameter). | Ranked element families by hull distance + symmetry preservation |
2. Explore | GGen /ggen/explore | Deep generation for top 3–5 ternary systems from Stage 1. | Relaxed CIFs, phase diagrams, stability ranking |
3. Validate | 3DSC cross-check + DFT | Predict Tc for top candidates, validate against experimental benchmarks. | Ranked shortlist with predicted Tc |
4. Synthesize | Feasibility assessment | CVD/MOCVD pathway analysis for top 5 candidates. | Synthesis recommendations |
CdI₂-type (P-3m1) — TMD backbone with vdW gap. M–X₂–X stacking. NbSe₂, TaS₂ families.
AlB₂-type (P6/mmm) — Honeycomb boride/nitride layers. MgB₂ prototype (Tc = 39 K bulk, highest ambient-pressure non-cuprate).
ThCr₂Si₂-type (I4/mmm) — Iron-pnictide backbone. ~30 known SCs, Tc up to 38 K in Ba₁₋ₓKₓFe₂As₂.
System | Template | X pool | Hypothesis |
|---|---|---|---|
Nb-Se-{X} | CdI₂-type | chalcogens (S, Te, Bi) | Extend best-known 2D SC family |
Ta-{X}-S | CdI₂-type |
Estimated compute: 4 systems × 50 candidates = 200 relaxations.
≥ 10 thermodynamically stable (hull ≤ 50 meV/atom) layered ternary candidates
≥ 3 candidates with predicted Tc ≥ 15 K
≥ 1 candidate with CVD/MOCVD synthesis feasibility
CVD precursor availability —
Monolayer vs. few-layer Tc suppression — how much Tc degrades from bulk to monolayer for each structural family
vdW gap engineering — intercalation or functionalization to boost Tc without breaking layer structure
Stage 1 ready to launch. GGen scout route updated with max_candidates parameter. Awaiting confirmation of parameter name/default from route update.
4d/5d TMs (Nb, Mo, W, V)
Isostructural TMD with heavier element |
Fe-Te-{X} | ThCr₂Si₂-derived | chalcogens (Se, S) | Iron-chalcogenide SC family |
Mg-B-{X} | AlB₂-type | main-group (Al, C, N) | MgB₂ analogs with ternary modification |
OpenedClosed after 3 months
Recovery action 019fb91f-6a76-78a4-b10b-7c3a01651d62 queued 2026-07-31 after prior action 019fb843 was reaped. Configuration is bounded to S/Te/Bi, max_stoichiometries=4, shallow_trials=2, max_steps=250, and hexagonal/trigonal scoring to stay within the 45-minute action reaper.
Prior scout action 019fb054-56be-7ff8-aba8-5e12fc0f8a1c was reaped by the 45-minute stale-action reaper without returning its result file. Recovery action 019fb87a-fabd-7149-adf3-c8481a914073 is queued with Ta-{Nb,Mo,W,V}-S, hexagonal targeting, seed 7312032, max_stoichiometries=4 and shallow_trials=3. The configuration caps generated trial structures at 48 (within the item’s 50-candidate ceiling) and should fit the reaper window.
Recovery action 019fb98d-6617-7810-9731-aa370144e944 succeeded and returned file a0df680e-baaf-40df-934e-642c6758b7c3. Four candidates were explored in each of Fe-S-Te and Fe-Se-Te; no on-hull, near-hull, or tetragonal target hits. Negative bounded-screen result; do not promote this family to Tc prediction.
Action 019fba69-6de8-7f4c-88dd-7cfe61bf5a8c completed successfully and returned result file f47c235b-2f0a-41a6-b69a-419846e26516. The bounded Mg-B-{Al,C,N} scan explored 12 formulas; only terminal Mg was a hexagonal target hit, so no valid Mg-B-X layered ternary advances to Tc prediction.
Beginning Stage 2 triage: retrieve Stage 1A–1D result assets, exclude non-ternary/negative screens, validate candidate structures, and rank any ≤50 meV/atom layered hits.
Cancelled by @mmoderwell — no candidate limit parameter on scout route at time of launch. Route now updated.
Stage 3 Tc slice completed on 2026-08-02. Nb3Se5S is the only confirmed structure-bearing candidate; live jv_supercon_tc_alignn estimate is 6.05943 K, with NbSeS and NbSe2 controls. Synthesis feasibility can now be scoped around Nb3Se5S, but do not treat the ML Tc as validated until EPC/phonon or experimental evidence is available. See artifact file 0a986875-b4f8-43a5-8c34-c9e69909e5f6.
Cancelled by @mmoderwell — no candidate limit parameter on scout route at time of launch. Route now updated.
Cancelled by @mmoderwell — no candidate limit parameter on scout route at time of launch. Route now updated.
Subsumed into restructured pipeline — CIF export now part of Stage 2 (Triage) and Stage 3 (Tc prediction).
Subsumed into restructured pipeline — DFT relaxation now part of Stage 3 (Tc prediction via DFT EPC).
Subsumed into restructured pipeline — EPC + Tc estimation now Stage 3.
Subsumed into restructured pipeline — synthesis recommendation now Stage 4.
Subsumed into restructured pipeline — deliverable now Stage 5 (Publish findings).
Stage 4 Nb3Se5S synthesis feasibility assessment
.mdEvidence-bounded CVD/MOCVD feasibility gate for the sole structure-bearing Nb3Se5S candidate: compositionally plausible NbSxSe2−x alloy, but generated Cm order and finished MoS2/WS2 stack compatibility remain unverified.
Stage 3 bounded Tc predictions and controls
.jsonAudited live-route Tc predictions for the validated Nb3Se5S GGen candidate, NbSeS layered control, and NbSe2 known-answer control. Includes route action IDs, prediction values, control error, observations, scientific limits, and EPC follow-up.
Bounded GGen scout found no publishable 2D ternary superconductor candidate
A reproducible negative result from the four-family GGen scout: six loose near-hull counts, but zero confirmed layered ternary candidates at the exact Stage 2 gate.
GGen scout results for Fe-Te-{X}
.jsonCandidate element scout results for fixed elements Fe, Te