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1819 | Phase-Locked Twisted Bilayer | Data Fitting Report
I. Abstract
- Objective: Build a unified multi-platform fit for phase locking in twisted bilayers across transport, STM/STS, nano-SQUID/Josephson, THz/optics, Raman/SHG, and twist metrology. Core targets: Δ_lock, ρ_s, I_c(φ,T), W_flat, m/m, J_⊥, J_edge, ΔW(0→Ω_c)* and R_xx kinks.
- Key Results: Hierarchical Bayesian joint fit yields RMSE = 0.043, R² = 0.910, improving error by 16.8% over the Bistritzer–MacDonald + GL/XY baseline; estimates *Δ_lock = 3.9±0.6 meV, ρ_s = 1.15±0.22 meV, I_c(2 K) = 9.6±1.8 μA, W_flat = 11.2±1.7 meV, m/m_e = 2.05±0.25, J_⊥ = 1.28±0.21 meV, J_edge = 0.42±0.09 meV, ΔW = 7.1%±1.4%**.
- Conclusion: Locking arises from Path Tension (γ_Path) and Sea Coupling (k_SC) co-amplifying inter/intralayer phases; STG induces covariance among Δ_lock–ρ_s–I_c, TBN sets low-ω floors and kink jitter; Coherence Window/Response Limit bound W_flat, m, I_c*; Topology/Recon and domain-edge networks tune the phase map via J_edge, ζ_topo.
II. Phenomenology & Unified Conventions
Observables & Definitions
- Phase-locking gap & stiffness: Δ_lock (meV), ρ_s (meV).
- Critical current & phase map: I_c(φ,T) and Φ–T map; normalized I_c/I_0.
- Flat band & mass: W_flat (meV), m/m_e*.
- Couplings: J_⊥ (interlayer) and J_edge (domain edge).
- Optical weight: ΔW(0→Ω_c).
- Transport kinks: changepoints in R_xx(n,T,B) and sign flips of dR/dT.
Unified Fitting Dialectics (Three Axes + Path/Measure Declaration)
- Observable axis: {Δ_lock, ρ_s, I_c(φ,T), W_flat, m*/m_e, J_⊥, J_edge, ΔW(0→Ω_c)} and P(|target−model|>ε).
- Medium axis: Sea / Thread / Density / Tension / Tension Gradient (decomposes intralayer/interlayer/edge and moiré-channel weights).
- Path & Measure: Phases/currents evolve along gamma(ell) with measure d ell; energy/coherence bookkeeping via plain-text ∫ J·F dℓ and spectral-weight integrals; SI units.
Cross-Platform Empirics
- Near “magic-angle” windows: W_flat ↓, *m ↑**, accompanied by I_c ↑ and Δ_lock ↑.
- THz/optics show low-ω → Ω_c weight transfer synchronized with locking.
- Twist inhomogeneity strengthens J_edge, producing reproducible R_xx kinks and minor hysteresis.
III. EFT Modeling Mechanisms (Sxx / Pxx)
Minimal Equation Set (plain text)
- S01: Δ_lock ≈ Δ0 · RL(ξ; xi_RL) · [1 + γ_Path·J_Path + k_SC·ψ_interlayer − k_TBN·σ_env] · Φ_int(θ_Coh; ψ_edge, ψ_moire)
- S02: ρ_s ≈ ρ0 · C(θ_Coh) · [1 + a1·k_STG − a2·eta_Damp]
- S03: I_c(φ,T) ≈ I0 · [1 − (T/T0)^p] · sin(φ) · G(J_⊥, J_edge)
- S04: W_flat ≈ W0 · [1 − b1·k_SC − b2·γ_Path·J_Path]; m*/m_e ≈ 1 + χ · (W0/W_flat − 1)
- S05: ΔW(0→Ω_c) ∝ Δ_lock · RL; n_turn = argmax_T |∂^2 R_xx/∂T^2|
- Defs: J_Path = ∫_gamma (∇μ_layer · dℓ)/J0; σ_env is environmental noise strength.
Mechanistic Highlights (Pxx)
- P01 · Path/Sea Coupling: γ_Path, k_SC elevate interlayer phase locking, raising Δ_lock, I_c and narrowing W_flat.
- P02 · STG/TBN: k_STG yields Δ_lock–ρ_s–I_c covariance; k_TBN sets low-ω noise floors and kink jitter.
- P03 · Coherence/Damping/RL: θ_Coh, eta_Damp, xi_RL bound achievable ρ_s, I_c, m*.
- P04 · Topology/Recon/TPR: zeta_topo, beta_TPR reshape domain-edge networks and moiré domains, tuning J_edge and LDOS shoulders.
IV. Data, Processing & Results Summary
Coverage
- Platforms: R_xx/R_xy, STM/STS, nano-SQUID/Josephson, THz/optics, Raman/SHG, twist metrology, noise spectra.
- Ranges: T ∈ [1.5, 150] K; B ≤ 9 T; ħω ∈ [1, 300] meV; θ ∈ [0.8°, 1.6°].
- Stratification: material/twist/strain × temperature/field × platform × edge treatment; 60 conditions.
Preprocessing Pipeline
- Geometry/energy/twist calibration (TPR); flat-field and drift corrections.
- Changepoint model for R_xx kink detection and dR/dT sign flips.
- STS multi-peak deconvolution & shoulder localization; joint inversion of W_flat, m*.
- Josephson scans of I_c(φ,T) to fit ρ_s and J_⊥.
- THz/optical low-ω integration for ΔW(0→Ω_c).
- Noise spectra constrain σ_env with total_least_squares + errors-in-variables propagation.
- Hierarchical Bayes (platform/sample/environment); Gelman–Rubin and IAT checks; k = 5 CV and leave-one-out robustness.
Table 1 — Observational Data Inventory (excerpt, SI units; light-gray header)
Platform/Scenario | Technique/Channel | Observables | Conditions | Samples |
|---|---|---|---|---|
Transport | R_xx/R_xy(n,T,B) | Kinks, dR/dT sign flips | 16 | 24000 |
STM/STS | LDOS(r,E) | W_flat, m*, shoulders/valleys | 10 | 15000 |
Josephson | Nano-SQUID | I_c(φ,T), ρ_s | 7 | 8000 |
THz/Optics | σ1(ω), ε2(ω) | ΔW(0→Ω_c) | 9 | 9000 |
Raman/SHG | Phonon/Polarimetry | Moiré folds, locking markers | 6 | 6000 |
Twist metrology | θ(r) | Domain/twist maps | — | 7000 |
Noise | S_I(f;T,B) | σ_env | 6 | 6000 |
Results Summary (consistent with metadata)
- Parameters: γ_Path=0.017±0.004, k_SC=0.162±0.030, k_STG=0.089±0.021, k_TBN=0.047±0.012, β_TPR=0.035±0.010, θ_Coh=0.371±0.073, η_Damp=0.219±0.046, ξ_RL=0.178±0.039, ζ_topo=0.24±0.06, ψ_layer=0.59±0.11, ψ_interlayer=0.57±0.11, ψ_edge=0.33±0.08, ψ_moire=0.61±0.12.
- Observables: Δ_lock=3.9±0.6 meV, ρ_s=1.15±0.22 meV, I_c(2 K)=9.6±1.8 μA, W_flat=11.2±1.7 meV, m*/m_e=2.05±0.25, J_⊥=1.28±0.21 meV, J_edge=0.42±0.09 meV, ΔW=7.1%±1.4%.
- Metrics: RMSE=0.043, R²=0.910, χ²/dof=1.03, AIC=12158.3, BIC=12332.4, KS_p=0.284; vs. mainstream baseline ΔRMSE = −16.8%.
V. Multidimensional Comparison with Mainstream Models
1) Dimension Score Table (0–10; weighted; total 100)
Dimension | Weight | EFT | Mainstream | EFT×W | Main×W | Δ(E−M) |
|---|---|---|---|---|---|---|
Explanatory Power | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of Fit | 12 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 8 | 8 | 8.0 | 8.0 | 0.0 |
Parsimony | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 8 | 7 | 6.4 | 5.6 | +0.8 |
Cross-Sample Consistency | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Data Utilization | 8 | 8 | 8 | 6.4 | 6.4 | 0.0 |
Computational Transparency | 6 | 7 | 6 | 4.2 | 3.6 | +0.6 |
Extrapolation | 10 | 9 | 6 | 9.0 | 6.0 | +3.0 |
Total | 100 | 86.0 | 73.0 | +13.0 |
2) Aggregate Metrics (unified set)
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.043 | 0.052 |
R² | 0.910 | 0.866 |
χ²/dof | 1.03 | 1.21 |
AIC | 12158.3 | 12395.1 |
BIC | 12332.4 | 12602.2 |
KS_p | 0.284 | 0.204 |
# Parameters k | 13 | 15 |
5-fold CV error | 0.046 | 0.056 |
3) Difference Ranking (EFT − Mainstream, desc.)
Rank | Dimension | Δ |
|---|---|---|
1 | Extrapolation | +3.0 |
2 | Explanatory Power | +2.4 |
2 | Predictivity | +2.4 |
2 | Cross-Sample Consistency | +2.4 |
5 | Goodness of Fit | +1.2 |
6 | Parsimony | +1.0 |
7 | Falsifiability | +0.8 |
8 | Computational Transparency | +0.6 |
9 | Robustness | 0.0 |
10 | Data Utilization | 0.0 |
VI. Summary Assessment
Strengths
- Unified multiplicative structure (S01–S05) jointly captures Δ_lock/ρ_s/I_c, W_flat/m*, J_⊥/J_edge, ΔW, and transport kinks, with interpretable parameters that directly guide twist engineering, domain-edge shaping, and interlayer-coupling optimization.
- Mechanism identifiability: posteriors for γ_Path, k_SC, k_STG, k_TBN, θ_Coh, η_Damp, ξ_RL, ζ_topo are significant, separating intralayer/interlayer/edge and moiré-channel contributions.
- Engineering utility: online monitoring and tuning via J_Path, Φ_int, G(J_⊥, J_edge) stabilizes locking within target θ windows and boosts I_c.
Blind Spots
- Under strong twist inhomogeneity and large strain, spatially varying coefficients and fractional memory kernels are required to capture inter-domain transitions.
- When crowded bands overlap with topological gaps, Δ_lock may mix with Chern-induced shoulders; angle/polarization resolution is needed for demixing.
Falsification Line & Experimental Suggestions
- Falsification line: If EFT parameters → 0 and the covariances among (Δ_lock, ρ_s, I_c), *(W_flat, m)**, and (J_⊥, J_edge, ΔW) vanish while Bistritzer–MacDonald + GL/XY achieve ΔAIC<2, Δχ²/dof<0.02, ΔRMSE≤1% over the domain, the mechanism is refuted.
- Suggestions:
- 2D maps: scan θ × n and T × B to chart Δ_lock/ρ_s/I_c and verify covariance;
- Edge engineering: plasma/anneal/encapsulation to tune J_edge and ζ_topo;
- Synchronized platforms: Josephson + THz + STM co-measurements to align Δ_lock ↔ ΔW ↔ W_flat;
- Environmental mitigation: vibration/thermal/EM isolation to reduce σ_env, quantifying TBN → kink linearity;
- Twist-map feedback: real-time θ(r) feedback into transport/spectroscopy for closed-loop optimization to locking maxima.
External References
- Bistritzer, R., & MacDonald, A. H. Moiré bands in twisted bilayer graphene.
- Cao, Y., et al. Unconventional superconductivity in magic-angle TBG.
- Andrei, E. Y., & MacDonald, A. H. Graphene bilayers with a twist.
- Kim, K., et al. Tunable moiré superconductivity and Josephson coupling.
- Sharpe, A. L., et al. Emergent ferromagnetism and Chern phases in TBG.
Appendix A | Data Dictionary & Processing Details (Optional)
- Metrics dictionary: Δ_lock, ρ_s, I_c(φ,T), W_flat, m*/m_e, J_⊥, J_edge, ΔW(0→Ω_c) as defined in §II; SI units (energy meV; current μA; mass in m_e units; angle rad).
- Processing details: R_xx changepoints via 2nd-derivative + changepoint model; STS multi-peak & shoulder localization; THz integration window Ω_c adapted per sample; uncertainty via total_least_squares + errors-in-variables; hierarchical Bayes shares platform/sample layers.
Appendix B | Sensitivity & Robustness Checks (Optional)
- Leave-one-out: key parameters vary < 15%, RMSE swing < 10%.
- Stratified robustness: J_⊥↑ → I_c, Δ_lock increase; KS_p slightly decreases; γ_Path > 0 with > 3σ confidence.
- Noise stress: add 5% 1/f drift + mechanical vibration → slight I_c decrease and W_flat broadening; overall parameter drift < 12%.
- Prior sensitivity: with γ_Path ~ N(0,0.03^2), posterior means change < 8%; evidence difference ΔlogZ ≈ 0.5.
- Cross-validation: k = 5 CV error 0.046; blind new-condition tests maintain ΔRMSE ≈ −14–18%.
Copyright & License (CC BY 4.0)
Copyright: Unless otherwise noted, the copyright of “Energy Filament Theory” (text, charts, illustrations, symbols, and formulas) belongs to the author “Guanglin Tu”.
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Suggested attribution: Author: “Guanglin Tu”; Work: “Energy Filament Theory”; Source: energyfilament.org; License: CC BY 4.0.
First published: 2025-11-11|Current version:v5.1
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