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0 votes
0 answers
45 views

How can a greater than 1 reflectance coefficient be explained in $\rm SiC$-$\rm SiO_2$ interface?

I ran a simulation using the Transfer Matrix Method to plot the R,T and A curves for a SiC->SiO2 interface. There's a region of incident energies where the |r|^2 I get is higher than 1 and the ...
Daniel's user avatar
  • 11
0 votes
1 answer
35 views

Ray separation in waveplates

In a birefringent medium, the ordinary and extraordinary rays have different Pointing-vector directions and, therefore, different propagation directions, since the direction of the Poyting-vector ...
Kubrik's user avatar
  • 47
0 votes
0 answers
37 views

Is the relativistic energy-momentum relation fundamental? [duplicate]

The following relativistic energy-momentum relationship is taken to be fundamental: $$E^2=p^2c^2+m_0^2c^4.\tag{1}$$ Let us specialize to massless particles ($m_0=0$) so that we have: $$E=p\ c.\tag{2}$$...
John Eastmond's user avatar
1 vote
0 answers
32 views

QFT view of lower light speed of light in medium [duplicate]

In classical EM theory, if we have a medium whose dielectric coefficient is independent of wavelengths (suppose we filter the incoming signal to a certain frequency band), then the waveform gets to ...
Meatball Princess's user avatar
0 votes
0 answers
27 views

How does an electromagnetic wave behave when it enters a medium with refractive index less than unity?

From what I am able to find, the phase velosity of the wave exceeds c, but the group velosity remains less than c. However, why does the wave form wavepackets after entering a medium with refractive ...
QuarkGP's user avatar
  • 11
3 votes
2 answers
132 views

Why is $c = \frac{1}{\sqrt{\mu_0 \epsilon_0}}$?

I'm sorry if this is a duplicate but I didn't find my answer. I'm currently studying maxwell's equations and I know that by comparing the wave equation for either the magnetic or the electric field \...
Axodarap's user avatar
15 votes
6 answers
7k views

Why color depends on frequency and not on wavelength? [duplicate]

To explain my question lets consider this example: The wavelength of light in a medium is $\lambda=\lambda_{0}/\mu$, where $\lambda_{0}$ is the wavelength in vacuum. A beam of red light ($\lambda_{0}=...
Devansh Mittal's user avatar
1 vote
0 answers
91 views

The speed of light in medium with different frequency

We know that the speed of light in vaccuum can be expressed as $c=\frac{1}{\sqrt{\mu_0\epsilon_0}}$ and thus the speed of light in vaccuum is thus $$v=\frac{1}{\sqrt{\mu\epsilon}}=\frac{c}{\sqrt{\...
Pck Tsp's user avatar
  • 83
6 votes
2 answers
926 views

Why does phase get kicked back during refraction?

I've just watched this video from 3Blue1Brown which explains how prisms works, but when he talks about the "phase kickback" that light undergoes when passing through a layer of a medium he ...
user8532377's user avatar
8 votes
2 answers
5k views

At what speed does information move through the atoms of a rigid object?

How fast does information travel on particles? I thought if you move a iron bar from one end it would take the speed of sound to move its other end. For example, theoretically if you hold an iron bar ...
J Frank's user avatar
  • 97
0 votes
1 answer
46 views

Help with dispersion relations for EM waves in anisotropic dielectric materials

I am really struggling to understand the following dispersion relations which we derived in class. For an electric field in the z-direction, we have: $$k^2_x + k^2_y = \frac{\omega^2}{c^2}n_z^2\tag{1}$...
Thomas's user avatar
  • 155
0 votes
2 answers
66 views

How to use the boundary conditions of electromagnetic waves to derive the refraction law of light?

In my book it says we can use the boundary conditions of electromagnetic waves to derive the refraction law of light. How to derive it?
Raffaella's user avatar
  • 353
0 votes
1 answer
58 views

Relativistic Effects on Electromagnetic Wave Propagation

So for a recent lab I had to calculate the length of a conductor by measuring the time it took a signal to reflect off of the open end. I used the very simple principle of $v=st$ and, knowing that the ...
Yasen Y.'s user avatar
0 votes
0 answers
103 views

Propagation of light in a time-varying refractive medium

Spatial gradients in the refractive index of a medium have an impact on the wavelength, frequency, and direction of waves propagating through them. What about media whose refractive index changes (...
trbabb's user avatar
  • 101
6 votes
3 answers
742 views

When designing antennas which speed of light should be used?

When calculating "antenna element length" should we use the speed of light in the "medium between transmitter and receiver (antenna)" or the speed of light in the "element ...
Duke William's user avatar

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