Questions tagged [polarization]
Polarization characterizes the oscillations in time the electromagnetic field is doing in the plane perpendicular to the propagation direction of a wave
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Rotation of electric field vector or polarization
Given a circularly polarized light field. I am using complex notation to represent the field,
$$\vec{E}(z=0, t) = \frac{1}{\sqrt2} [ \hat{x} (\cos(\omega t) - i \sin(\omega t)) + \hat{y} (i\cos(\omega ...
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"Remembering" the polarization in the BB84 protocol
I am trying to understand the essence of the BB84 protocol and by watching this video,
https://www.youtube.com/watch?v=uiiaAJ3c6dM&t=171s
I cannot manage to understand the following. Alice is ...
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Why is polarization $\mathbf{P}$ proportional to the $\mathbf{E}$ field, but magnetization $\mathbf{M}$ proportional to the $\mathbf{H}$ field?
Why is the polarization intensity $\mathbf{P}$ proportional to $\mathbf{E}$ (electronic filed), while the magnetization intensity $\mathbf{M}$ proportional to $\mathbf{H}$ (magnetic filed), when the ...
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Shadow from Direct Sunlight Visibly Brighter When Viewed Through Polzarized Lens?
I searched this site for about 10-20 minutes using both Google and its built-in search. Wasn't able to find any question similar to this one.
I've taken Physics 1+2 and an introduction to modern ...
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Can spin really be measured in an arbitrary direction?
If I am in the computational basis (given by unit vector ${z}$) and have a ket $|0\rangle$, and I have $\sigma = (\sigma_x, \sigma_y, \sigma_z)$, the Pauli matrices, then my ket is an eigenfunction of ...
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A "plausible mistake" in Born and Wolf book
I am reading Born and Wolf book Chapter 1 and specifically section 1.6 "Wave propagation in stratified medium" (wrt. 7th edition). I think that there is some error in the equation which is ...
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Why is no flickering observed in polarized filters?
Consider a computer screen which emits horizontally polarized light and a polarized filter. If you rotate the filter 45° relative to the screen, then it will let through roughly 50% of the light from ...
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Calculating polarization
In this paper, authors prove experimentally that it is possible to create time-crystals. It is my understanding, reading the paper, that they have measured the polarization of the system, however, I ...
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What happens if you try to polarize a photon in the time direction?
In the comments on a video explaining some part of quantum mechanics, there was a comment about rejecting unphysical solutions to some equation, such as time-polarized photons.
As far as I'm aware, ...
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Are Maxwell's equations inconsistent? [closed]
Maxwell's equations in linear homogeneous matter:
$$
\begin{eqnarray}
\nabla\cdot\mathbf{E}&=&\frac{\rho}{\epsilon},\tag{1}\\
\nabla\times\mathbf{E}&=&-\frac{\partial\mathbf{B}}{\...
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Twisting a laser with the Quantum Zeno Effect
I thought of an experiment in QM with a predicted result that seems kind of absurd to me, so I want to know what I am missing in my mental model. I tried to perform the experiment using a consumer-...
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Computational methods to calculate piezoelectric tensors from Berry phase and phonon approaches [closed]
Recently, I have been exploring methods for computationally calculating piezoelectric properties(tensors), such as Berry phase and phonon-based approaches. I would greatly appreciate any insights into ...
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How is the polarization transfer formula in hyperon decay derived?
In the decay process of spin-1/2 hypron to spin-1/2 baryon and spin-0 meson (such as $\Lambda \to p + \pi$), the polarization vector $\mathbf{P}_D$ of the daughter baryon is given in terms of the ...
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Impact of a non-ideal Beam Splitter (BS) in QKD protocol
I’ve noticed that in the BB84 protocol the Beam Splitter (BS) is typically assumed to be ideal. I'm wondering whether this is a reasonable approximation, or if the imperfections of real BS devices ...
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Feynman rules for outgoing photon
This question is related to the Feynman rules of QED.
A general photon state is characterized by its momentum and spin, and it can be written as $$|k,\varepsilon\rangle\equiv\varepsilon^\mu a_\mu^\...
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