# Questions tagged [dispersion]

Dispersion refers to the frequency dependence of the properties of a wave.

296 questions
Filter by
Sorted by
Tagged with
16 views

### What's is the relation between band structure and dispersion relation?

I'm currently studying band structures, and I'm a little bit confused about how the band structure is related to the dispersion relation. Are they they same thing?
15 views

### Degree of dispersion of a simple slit spectroscope

To calculate the dynamic range of a spectroscope + CCD instrument, you first need to calculate the degree of dispersion $\frac{d\lambda}{pixel}$. I have some trouble understanding the model solution ...
28 views

### Why the fields of the quasi-TEM mode of microstrip line tend to concentrate in the dielectric as frequency goes higher?

A microstrip line is a waveguiding structure as shown below: Because of the inhomogeneity, the fundamental mode of propagation is a quasi-TEM mode, which means that the z components of the E and H ...
12 views

### Effective refractive index and refractive index [duplicate]

Is there any relation connecting between the effective refractive index $N$ and the refractive index $n$ in waveguide?
18 views

### Creating Different Colours From A Pulsed Monochromatic Light Source

I am currently learning about fibre optic communications, which I understand use pulsed laser sources to generate a "bitstream" to send through the fibre using some form of pulse width ...
30 views

### How to determine crystallographic directions from dispersion relation graph? [closed]

How does one determine the crystallographic directions in a phonon dispersion relation graph (e.g. see below)? I know it has something to do with the first Brillouin zone in reciprocal space (see ...
31 views

### Dispersive relation in quantum wave mechanics

Question 2. For nonrelativistic free particle $E=\frac{p^{2}}{2m}$ and using the de Broglie relations the corresponding dispersive relation becomes $$\omega(k)=\frac{\hbar k^{2}}{2m}$$ Then following ...
60 views

### What is the intuitution behind a wave with zero wavenumber?

I was recently solving a physics problem that gave you the electric field $$E(x, y, z, t) = E_{0}cos(k_{y}y + \psi_{y})sin(k_{x}x-{\omega}t)\hat{z}$$ and the question asked for a variety of things ...
40 views

### Why is String Stiffness Proportional to the Fourth Spatial Derivative of String Displacement?

I recently watched a lecture on dispersive medium. I understand that if you disregard the idea that a string is ideal, you must add a stiffness factor into the wave equation. From that you can derive ...
76 views

### Validity of hydrodynamic description

Spontaneous thermal fluctuations occur at microscopic level in liquids. It is said that hydrodynamic description is valid in the long wavelength and low frequency limit. So, to depict the thermal ...
4k views

### Why are red and blue light refracted differently if they travel at the same speed in the same medium?

When I look at Snell's law $\frac{\sin\theta_2}{\sin\theta_1} = \frac{v_2}{v_1} = \frac{n_1}{n_2}$ I don't see any reference to wavelength. If red and blue have the same speed in the same medium, why ...