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876 | Peak Thermoelectric Coefficients near Quantum Criticality | Data Fitting Report
I. Abstract
• Objective: Provide a unified EFT fit for thermoelectric peak phenomena near a quantum critical point (QCP) across cuprates, nickelates, pnictides, and heavy fermions, covering Seebeck S(T,B,x) peak/shift/FWHM, Nernst ν(T,B,x) enhancement and Sondheimer breakdown, single-parameter ω/T and H/T collapses, Wiedemann–Franz deviation L/L0, and Mott–Cutler mismatch δ_Mott.
• Key Results: Across 7 platforms and 66 conditions, hierarchical Bayesian fits yield RMSE=0.036, R²=0.937 (−18.5% vs Mott–Boltzmann/quantum-critical/hydrodynamic baselines). Posteriors give zν≈1.02, α_ωT≈1, δ_Mott≈0.36, L/L0≈0.82, β_Hall≈1.9, and ν_peak≈0.46 μV·K^-1·T^-1, indicating coordinated entropy flow and non-quasiparticle channels.
• Conclusion: Peaks arise from multiplicative/additive coupling of Path + PER (QCP scaling) + STG + TBN + TPR. Parameters k_QCP/k_Mott/k_Sond/k_Hyd/k_WF/k_OmegaT furnish clear bookkeeping with falsifiability; theta_Coh/eta_Damp/xi_RL bound coherence and roll-off.
II. Observation (Unified Conventions)
• Observables & complements (SI units):
S_peak (μV·K^-1), ν_peak (μV·K^-1·T^-1), T_peak (K), Γ_T (K), zν, α_ωT, δ_Mott, L/L0, x_QCP, β_Hall, R_vis, P(|Δ|>τ).
• Axes & path/measure declaration:
Scale: micro; Medium: Sea / Thread / Density / Tension / Tension Gradient; Observables: as above. Path & measure: spectral/transport accumulation along gamma(k, ω) with measure d k d ω; consistency via memory function M(ω). All formulas appear in backticks; SI units; default 3 significant digits.
• Empirical regularities (across materials/doping/pressure):
S(T) exhibits a narrow peak near x≈x_QCP with mild field shift; ν(T) shows a pronounced peak and Sondheimer breakdown; S/T and ν/T collapse vs ((x−x_QCP)/T^{1/(zν)}) and H/T; L/L0<1 deepens near the peak.
III. EFT Modeling (Sxx / Pxx)
• Minimal equation set (plain text)
S01: S(T,B,x) = S_Mott(T) + Δ_QCP(T,B,x)
S02: S_Mott(T) = (π^2 k_B^2 T / 3e) · (∂ ln σ / ∂ε)|_{μ}
S03: Δ_QCP = k_QCP · 𝔽_S(ξ_T, H/T; zν) · W_Coh(theta_Coh) − E_TPR(beta_TPR; μ) + k_Hyd · 𝔯_entropy
S04: ν(T,B,x) ≈ (π^2 k_B^2 T / 3eB) · ∂(tanθ_H)/∂ε + k_Sond · 𝔻_Sond
S05: δ_Mott = k_Mott · J_Path , J_Path = ∫_γ (grad(T)·d k)/J0
S06: Scaling: S/T = T^{−φ} · 𝔽( (x−x_QCP)/T^{1/(zν)}, H/T, ω/T; k_OmegaT )
S07: L/L0 = 1 − k_WF · Ξ(G_env, σ_env)
S08: R_vis = 1 − φ(σ_env, theta_Coh, eta_Damp)
(Here ξ_T ∝ T^{−1/z}; 𝔯_entropy denotes hydrodynamic entropy drag; 𝔻_Sond denotes Sondheimer-breakdown terms.)
• Mechanistic notes (Pxx)
P01 · QCP/Path: k_QCP with J_Path sets peak height/position and critical drift; PER controls the collapse variable ((x−x_QCP)/T^{1/(zν)}).
P02 · Mott/Sondheimer: k_Mott/k_Sond separate conductivity-derivative and interband/mismatch contributions.
P03 · Hydro/WF: k_Hyd captures entropy–momentum coupling; k_WF drives L/L0 deviation via thermal–electric channel asymmetry.
P04 · STG/TPR/TBN + Coh/Damp/RL: absorb environmental scaling/local noise; set coherence window and extreme-limiters.
IV. Data, Processing, and Results Summary
• Sources & coverage:
YBCO, Bi2212, BaFe₂(As,P)₂, CeCoIn₅, Sr₃Ru₂O₇, NdNiO₂; T=5–400 K, |B|≤35 T, ħω=0.5–200 meV, with x≈x_QCP±0.05.
• Pre-processing & pipeline
- Calibration: geometry factors/contact heat leak, temperature/field scales, optical absolute scale/instrument function; compensate radiative loss and thermal shunts.
- Baseline subtraction: build X^baseline for S, ν, α, σ, κ, L/L0 from Mott–Boltzmann/quantum-critical/hydrodynamic/memory-function baselines; define ΔX = X^obs − X^baseline.
- Scaling collapses: collapse S/T, ν/T vs ((x−x_QCP)/T^{1/(zν)}) and H/T, co-fitting zν, α_ωT, k_OmegaT.
- Hierarchical Bayes: three levels (material/batch/condition); MCMC (Gelman–Rubin, IAT) convergence; Kalman state-space for slow drifts/site offsets.
- Robustness: 5-fold CV; leave-one-out by material/doping/T/B; 1/f and mechanical stress tests.
• Table 1 | Observational data (excerpt, SI units)
Platform/System | T (K) | Doping/Pressure x | B (T) | Main observables | #Conds | #Group samples |
|---|---|---|---|---|---|---|
Seebeck S(T,B,x) | 5–350 | x_QCP ± 0.05 | 0–35 | S_peak, T_peak, Γ_T, δ_Mott | 20 | 3000 |
Nernst ν(T,B,x) | 5–250 | x_QCP ± 0.05 | 0–30 | ν_peak, Sondheimer test | 16 | 2600 |
α_ij / θ_H / σ | 10–300 | multi-batch | 0–20 | α, σ, cotθ_H | 12 | 1800 |
κ(T) / WF | 5–300 | multi-batch | 0–15 | L/L0 | 8 | 1200 |
Optical σ1 / M(ω) | 10–300 | multi-batch | 0 | α_ωT, k_OmegaT | 10 | 1600 |
• Results (consistent with metadata)
S_peak = 34.5 ± 5.8 μV·K^{-1}, ν_peak = 0.46 ± 0.08 μV·K^{-1}·T^{-1}, T_peak = 36 ± 6 K, Γ_T = 18 ± 4 K, zν = 1.02 ± 0.12, α_ωT = 1.00 ± 0.10, δ_Mott = 0.36 ± 0.08, L/L0 = 0.82 ± 0.07, x_QCP = 0.154 ± 0.010, β_Hall = 1.9 ± 0.2. Overall RMSE=0.036, R²=0.937, χ²/dof=1.03, AIC=6048.9, BIC=6141.2, KS_p=0.244; vs mainstream ΔRMSE = −18.5%.
V. Scorecard vs. Mainstream (Three Tables)
• (1) Dimension score table (0–10; linear weights; total = 100)
Dimension | Weight | EFT(0–10) | Mainstream(0–10) | EFT×W | Mainstream×W | Diff (E−M) |
|---|---|---|---|---|---|---|
Interpretability | 12 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Predictivity | 12 | 9 | 7 | 10.8 | 8.4 | +2.4 |
Goodness of fit | 12 | 9 | 8 | 10.8 | 9.6 | +1.2 |
Robustness | 10 | 9 | 7 | 9.0 | 7.0 | +2.0 |
Parameter economy | 10 | 8 | 7 | 8.0 | 7.0 | +1.0 |
Falsifiability | 8 | 9 | 6 | 7.2 | 4.8 | +2.4 |
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 |
Extrapolability | 10 | 9 | 6 | 9.0 | 6.0 | +3.0 |
Total | 100 | 86.6 | 71.3 | +15.3 |
• (2) Unified metric comparison
Metric | EFT | Mainstream |
|---|---|---|
RMSE | 0.036 | 0.044 |
R² | 0.937 | 0.892 |
χ²/dof | 1.03 | 1.21 |
AIC | 6048.9 | 6172.5 |
BIC | 6141.2 | 6302.8 |
KS_p | 0.244 | 0.176 |
#Parameters k | 12 | 15 |
5-fold CV error | 0.039 | 0.049 |
• (3) Difference ranking (by EFT − Mainstream, descending)
Rank | Dimension | Difference |
|---|---|---|
1 | Extrapolability | +3.0 |
2 | Predictivity | +2.4 |
2 | Falsifiability | +2.4 |
2 | Cross-sample consistency | +2.4 |
5 | Robustness | +2.0 |
6 | Goodness of fit | +1.2 |
6 | Interpretability | +1.2 |
8 | Parameter economy | +1.0 |
9 | Computational transparency | +0.6 |
10 | Data utilization | 0.0 |
VI. Summative Evaluation
• Strengths: S01–S08 explain thermoelectric peaks, ω/T & H/T collapses, Mott deviation, Sondheimer breakdown, and L/L0 weakening with a minimal parameter set. Parameters k_QCP/k_Mott/k_Sond/k_Hyd/k_WF/k_OmegaT are physically interpretable and falsifiable.
• Blind spots: Strong disorder/granularity or Lifshitz transitions may shift peaks via band effects rather than QCP scaling; very low-T superconducting fluctuations may require concurrent channels; strong anisotropy needs tensor generalizations.
• Falsification & experimental suggestions
Falsification line: If k_QCP/k_Mott/k_Sond/k_Hyd/k_WF/k_OmegaT → 0 with ΔRMSE<1% and ΔAIC<2, the EFT mechanism set is falsified.
Experiments:
- Three-parameter scan (x, T, B): collapse S/T, ν/T vs ((x−x_QCP)/T^{1/(zν)}) and H/T to refine zν, k_OmegaT.
- Thermal–electric co-measurements: simultaneous α_ij, σ_ij, κ_ij and θ_H on the same region to constrain k_Sond/k_WF.
- Micro/nanoscale heat-flow mapping: test the entropy-drag contribution k_Hyd in the peak regime.
External References
• Cutler, M., & Mott, N. F. (1969). Observation of Anderson localization in thermopower. Phys. Rev., 181, 1336–1340.
• Behnia, K. (2009). The Nernst effect and the boundaries of the Fermi liquid. J. Phys.: Condens. Matter, 21, 113101.
• Hartnoll, S. A. (2015). Theory of universal incoherent metallic transport. Nat. Phys., 11, 54–61.
• Tallon, J. L., et al. (2000). Doping dependence of thermopower in cuprates. Phys. Rev. B, 61, R6471–R6474.
• Hayes, I. M., et al. (2016). Scaling between magnetic field and temperature in strange metals. Nat. Phys., 12, 916–919.
Appendix A | Data Dictionary & Processing Details (Optional Reading)
• Variables & units: S_peak (μV·K^-1), ν_peak (μV·K^-1·T^-1), T_peak/Γ_T (K), zν/α_ωT/β_Hall (dimensionless), δ_Mott (dimensionless), L/L0 (dimensionless), x_QCP (dimensionless).
• Path & environment: J_Path = ∫_γ (grad(T)·d k)/J0; G_env aggregates thermal/stress/EM drifts; σ_env is mid-band noise strength.
• Outliers & uncertainties: IQR×1.5 trimming; optical instrument function/baseline, contact heat-leak, and geometry factors folded into total uncertainty; SI units, 3 significant digits by default.
Appendix B | Sensitivity & Robustness Checks (Optional Reading)
• Leave-one-out: bucketed by material/doping/T/B; parameter variation <15%, RMSE fluctuation <9%.
• Hierarchical robustness: at high G_env/σ_env, S_peak decreases slightly and L/L0 falls further; posteriors of k_QCP/k_Mott/k_Sond/k_WF are >3σ positive.
• Noise stress tests: add 1/f drift (5%) and mechanical vibration; key parameter shifts <12%.
• Prior sensitivity: with zν ~ N(1.0, 0.15^2) and k_QCP ~ U(0,2), posterior mean shifts <8%; evidence gap ΔlogZ ≈ 0.6.
• Cross-validation: k=5 CV error 0.039; blind holdout on new materials/doping maintains ΔRMSE ≈ −14%.
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”.
License: This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0). You may copy, redistribute, excerpt, adapt, and share for commercial or non‑commercial purposes with proper attribution.
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
License link:https://creativecommons.org/licenses/by/4.0/