Optical Material Models

FDTD-Ready Optical Material Model Database

Compact rational-pole and critical-point dielectric-function models for broadband time-domain electromagnetic simulations.

June 2026 release — 405 source-specific records · 60 material labels · 3929 centered-ADE-ready exports.

Each downloadable entry provides a compact PoleResidue dielectric model, source-data traceability, fitting-error indicators, and a simulation-oriented readiness label for FDTD users.

FDTD-ready means a valid PoleResidue JSON export, passive response on the fitted grid, available model-response curve, and centered-ADE readiness at CFL = 0.75.

Using the downloaded models

Select a material, reference record, and model order.
Download the PoleResidue JSON model.
Use the JSON model in a compatible solver, or validate it with the MATLAB 1D FDTD reference example.

The MATLAB example reads a downloaded PoleResidue JSON file, runs a simple 1D dispersive-film FDTD test, and optionally compares reflection, transmission, and absorption against a transfer-matrix reference.

Full methodology, fitting statistics, and accuracy benchmarks →

Download MATLAB 1D FDTD example

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Browse models

Select a material, reference record, and model order.

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Material class Search material Material Reference record Model order

Material classes are practical database groupings rather than strict electronic-structure labels. Mixed-valence and phase-change oxides are grouped with semiconducting/oxide materials unless primarily used as metallic conductors.

Recommended model

Candidate models at selected N

Optical constants and model response

Use the plot-quantity selector to switch between optical constants and permittivity. Filled markers show experimental database points; optional open markers show the fitting grid.

Mathematical model definitions

PoleResidue JSON / rational-pole (RP)

ε_JSON(ω) = ε_∞ − ∑_m=1^M [ c_m/(iω + a_m) + c_m^*/(iω + a_m^*) ], Re(a_m) < 0.

This is the native convention used by the exported JSON files and the MATLAB reference code, under the exp(−iωt) time convention. Here a_m and c_m are the pole and residue stored in the JSON file; passive poles have negative real parts and should not be sign-flipped.

Critical-point fitting ansatz (CP)

ε_CP+(ω) = ε_∞ + ∑_ℓ=1^N_CP A_ℓ exp(iφ_ℓ) [(Ω_ℓ − ω) − iΓ_ℓ]^−p_ℓ, ω > 0, Γ_ℓ > 0.

Ω_ℓ, Γ_ℓ, A_ℓ, φ_ℓ, and p_ℓ denote the critical-point energy, broadening, strength, phase, and line-shape exponent. The CP expression is used as a fitting ansatz only.

Released CP-family entries are converted to the same finite PoleResidue JSON convention used above: ε_JSON(ω) = ε_∞ − ∑_m [c_m/(iω+a_m) + c_m^*/(iω+a_m^*)], with Re(a_m) < 0. The fractional-power CP term is not stored directly as the FDTD update model.

Record metadata