Optics of Polarized Light

Some of the basic facts of optics pertaining to ellipsometry will be presented briefly in this and the following subsections. Detailed treatment of the optical principles and the derivation of the equations for the reflection and the refraction of light can be found in standard textbooks on optics or electromagnetic radiation. A short summary of optical principles for ellipsometry was presented in a previous review on ellipsometric optics with special reference to electrochemical systems by the present author.  

The propagation of light waves in a nonabsorbing medium can be described by the oscillating electric field 

For the p component of the light, the reflection coefficient rg at the interface between i and j is given by 

For a light-absorbing medium, such as metals and semiconductors, the refractive index is complex, n = n — ik. For a (dielectric) medium which does not absorb light, the imaginary part of the refractive index is zero, A = 0. Therefore, the refractive index for a transparent medium is real. The magnitude of k is an index of light attenuation in the medium and is related to the absorption coefficient a by the relation a = Ank/X. Often, n and k are called the optical constants of a material.  

When at least one of the refractive indices n, and n, is complex, the reflection coefficients, Eqs. (2a) and (2b), become complex and can be written in terms of real modulus and phase factor. The phase factor of a reflection coefficient amounts to the 

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