newAD2 - optical characterization software

Sellmeier formula

modelname

Sellmeier

Real part of dielectric function is described by two parameters \(B_1, \lambda_1\). Imaginary part is zero: $$ \varepsilon_{r} = 1 + \frac{B_1 \lambda^2 }{ \lambda^2 - \lambda_1^2} \,. $$

attributes

• A - Adds parameter \(A\).
• eV - Parameterization using \(N_1\) and \(E_1\) instead \(B_1\) and \(\lambda_1\): $$ \varepsilon_r = A + \frac{2}{\pi} \frac{N_1}{E_1^2 - E^2} \,. $$
• number_of_terms - Adds terms and corresponding parameters \(B_2, \lambda_2, \dots\) $$ \varepsilon_r = A + \frac{B_1 \lambda^2 }{ \lambda^2 - \lambda_1^2} + \frac{B_2 \lambda^2 }{\lambda^2 - \lambda_2^2} + \dots \,. $$

Example

media:
  f = Sellmeier:A:2

newAD2> par
      Af = 1          fixed [1,inf)
     B1f = 1          fixed [0,inf)
lambda1f = 100        fixed (0,inf) nm
     B2f = 0          fixed [0,inf)
lambda2f = 110        fixed (0,inf) nm
newAD2>