Equation

According to Sadao Adachi J. Appl. Phys. Vol. 58, No.3, (1985) R1 the real part of the refractive index n of AlAs below the band gap edge can be expressed by:

with

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

• n - (real part) of the refractive index
• λ - vacuum wavelength
• h = 6.626 10 ^-34 Js - Planck´s constant
• c = 2.998 10⁸ m/s - speed of light in vacuum
• hc/λ - photon energy
• A₀ = 25.3 - fitted constant
• B₀ = - 0.8 - fitted constant
• E₀ = 2.95 eV - fundamental band gap at Γ-point
• E₀ + Δ₀ = 3.25 eV with Δ₀ - spin-orbit splitting energy