Optical Material Models

FDTD-Ready Optical Material Model Database

This page lists compact analytic dielectric-function models for time-domain electromagnetic simulations. The two model families are rational-pole (RP) models and critical-point (CP) models.

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Mathematical model definitions

Rational-pole (RP) model

The RP representation is

ε_RP(z) = ε_∞ + Σ_j=1^N[ r_j/(z − p_j) + r_j^*/(z − p_j^*) ].

Here z is the normalized complex-frequency variable, p_j is a complex pole, r_j is the corresponding residue, and N is the number of pole pairs.

Critical-point (CP) model

The CP representation is

ε_CP(ω) = ε_∞ + Σ_j=1^N[ c_jΩ_j/(Ω_j − ω − iΓ_j) + c_j^*Ω_j/(Ω_j + ω + iΓ_j) ], with Ω_j > 0 and Γ_j > 0.

Here Ω_j is the transition frequency, Γ_j is the damping rate, c_j is a complex coefficient, and N is the number of CP terms.

For each selected order N, the table reports the model family, RMS error, FDTD-readiness status, and the available PoleResidue JSON file.

FDTD-Ready Optical Material Model Database

Mathematical model definitions

Rational-pole (RP) model

Critical-point (CP) model

Recommended model

RP vs CP model

Optical constants and model response

Record metadata