Problem 9.22 Calculate the reflection coefficient for light at an air-to-silver inter- face (μ₁ = μ₂ = µ0, €1 = €0,σ = 6 × 107 (2· m)¯¹), at optical frequencies (@ = 4 × 1015/s).

A11

Salt absorbs in the infrared. The complex dielectric constant at wavelength 60µm is -16.8 + i91.4. Calculate the absorption coefficient and the reflectivity at normal incidence at stated wavelength, knowing that 5. E = Er + iɛ¡ ɛ = n? n = n, + in; 2wnį a = 1 |n R = In + 1 where e is the dielectric constant, n is the refractive index, a is the absorption coefficient and R is the reflectivity.

A colloid consists of particles of one type of substance dispersed in another substance. Suspensions of electrically charged microspheres (microscopic spheres, such as polystyrene) in a liquid such as water can form a colloidal crystal when the microspheres arrange themselves in a regular repeating pattern under the influence of the electrostatic force. Colloidal crystals can selectively manipulate different wavelengths of visible light. Just as we can study crystalline solids by using Bragg reflection of x rays, we can study colloidal crystals through Bragg scattering of visible light from the regular arrangement of charged microspheres. Because the light is traveling through a liquid when it experiences the path differences that lead to constructive interference, it is the wavelength in the liquid that determines the angles at which Bragg reflections are seen. In one experiment, laser light with a wavelength in vacuum of 650 nm is passed through a sample of charged polystyrene…