L4

Question 1

Dispersion

Answer 1

Phenomenon where the speed of light / refractive index varies with wavelength.

Question 2

Polarization and Magnetization

is there a name of this effect and is it valid in general?

Answer 2

P & M depend on the history of E and H.

Question 3

Fourier Transform

Answer 3

Used to pass into frequency domain.

Question 4

Susceptibility

add information or delete

Answer 4

Complex susceptibility has real and imaginary parts.

tbd

Question 5

Lorentz Model

Answer 5

Lorentz model describes a damped harmonic oscillator. (Origin of dispersion).

Question 6

Drude Model

Answer 6

Simplified Lorentz model: electrons bounce off ions.

Question 7

Kramers-Krönig Relations

Answer 7

Relates real and imaginary parts of susceptibility.

Question 8

Index of Refraction

Answer 8

Complex and frequency-dependent.

Question 9

Helmholtz Equation

Answer 9

Wave equation with dispersion.

Question 10

Attenuation Coefficient

Answer 10

α is the attenuation/absorption coefficient.

Question 11

Sellmeier Equation

Answer 11

Approximates optical properties in transparent regions.

Question 12

Phase and Group Velocity

Answer 12

Phase velocity can be faster than group velocity.

Question 13

Plasmons

Answer 13

Collective oscillations of electrons in metals.

Question 14

Physical Origins of Dispersion

Answer 14

• Depends on material and frequency
• e.g., plasmons, ionic vibrations

Question 15

Prisms and Dispersion

Answer 15

Different glass types show different dispersion of white light.