Sellmeyer equation

In the energy range below or near the fundamental absorption edge the dispersion of the refractive index n(λ) of GaAs can be calculated by the first-order Sellmeier equation:

In this equation the symbols and constants have the following meaning in the case of GaAs at room temperature:

• λ - vacuum wavelength in µm
• A = 8.950 - empirical coefficient
• B = 2.054 - empirical coefficient
• C² = 0.390 - empirical coefficient