# Exercise 5.2.3 Attenuation of Light

| Starting from
Ex | = | exp – | w · k · x c | · exp[ i · (kx · x – w · t)]
--- | --- | --- | --- | ---
|  | Decreasing amplitude | Plane wave
|  | Give maximal values for k (damping constant, attenuation index, extinction coefficient) if a penetration depth of 1m, 100 m 104 m is specified for the light intensity.
|  | Calculate what that would mean in terms of only e'' or only e''.
|  | Discuss the results with respect to the complex index of refractions of Si and the dielectric function of GaAs as given in this link for frequencies above and below the band gap (after you located the band gap by straight thinking).
| Link to the solution

With frame

5.2.3 The Complex Index of Refraction

Solution to Exercise 5.1-1: Derivation of Snellius Law

Solution to Exercise 5.2-1: Fresnel Equations and LEDs

Complex Index of Refraction of Silicon

Solution to 5.2-3: Attenuation of Light

Solution to Exercise 5.2-3: Rayleight Scattering

Solution to 5.2-4: Fresnel Equations and Polarization

© H. Föll (Advanced Materials B, part 1 - script)