Abstract
Accurate values of the refractive index of n‐type InP samples have been measured at two wavelengths, n = 0.633 μm and 1.15 μm, using a near‐Brewster‐angle reflectivity technique. For highly doped samples (carrier concentration ≳1018 cm−3) a relationship between carrier density and refractive index has been observed which can be explained in terms of conduction band filling.