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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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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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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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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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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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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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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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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Rayleigh-Jeans criteria in cavity radiation requiring 2 possible states of polarization
Reference to question is p. 9 in Eisberg, Resnick's
Quantum Physics of Atoms (1985). Dealing with
the "allowed values of the frequency in a 1-dimensional cavity of length $a$": I do not ...
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Why the polarization vectors must be orthogonal to the wave vector $\textbf{k}$?
M. Srednick in his book "quantum field theory" says on page 341 that
"In order to satisfy the Coulomb gauge condition $(\nabla\cdot \textbf{A}=0)$, the polarization vectors must be ...
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Calculation of visibility in Young's double slit experiment [closed]
I am working on a homework problem that asks me to calculate the visibility in Young's double slit experiment.
A monochromatic and linearly polarized light is used in a Young’s double slit experiment....
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Sun turns blue when seen through a crossed polariser/analyser
It was sunset, and we were looking at the sun through our polariser/analyser setup. When the angle between P and A was zero, the sunset looked normal (albeit with an expected reduction in brightness).
...
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Electric field of bound charges
I'm a physics student taking a first course on electromagnetism. I can't figure out how bound charges (or polarization charges) must be thought of. As I've thought to understood until now, in ...
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X-effect from Variable ND Filter photography
I’m trying to understand what’s happening when using a variable ND filter in photography.
A variable ND filter is placed in front of the lens to control the amount of light that reaches the sensor. It ...
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How does polarization manifest on the level of the quantum numbers?
Polarized light (or any EM wave) works by having an unidirectional orientation of the transverse EM waves. Fine, but that is a description of light (EM radiation) by EM fields. Deeper with a layer, we ...
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Correct definition of right-circularly polarized and left-circularly polarized
This is a simple question. I am just wondering about the correct definition of left and right circularly-polarized light. I thought that if I point my thumb in the direction of propagation, then in a ...
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Circular polarized light on a polarizer
I just studied polarization which made me curious.
What will be the difference observed when circular polarized light is incident on a polarizer compared to that of unpolarzised light?
What will be ...
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How many degrees of freedom required to describe the electromagnetic response of a linear isotropic material?
I am confused about complex permittivity, permeability, and conductivity.
My Question:
Ultimately I am trying to figure out what is the minimum (and maximum) number of degrees of freedom needed to ...
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Should/can one describe the angular momentum carried by a Photon as a 2 dimensional Hilbert space analogous to an electron spin?
I am currently trying to wrap my head around electron photon interaction processes in Atoms, as for example described here. In particular I am interested in the dependency of the angle between photon ...
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Can the "Three Polarizer Paradox" be explained classically?
I recently learned of the Three Polarizer Paradox:
If two polarizing films are aligned in the same direction light from
the first polarizer passes through the second. If the polarizers are
opposed at ...
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Lorentz invariance in scattering amplitudes involving gravitons
Let's consider a 2-to-2 scattering $$(p_1+p_2) \rightarrow (p_3+p_4).$$
Usually, the squared transition amplitude $|\mathcal{M}|^2$ can be expressed fully in terms of the Mandelstam variables
$$s=(p_1+...
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Sum of gluon polarizations in polarised Drell-Yan
Let's consider the polarised Drell-Yan process, in particular the process
$$
q_1(p_1,s_1)+g(p_2)\to \gamma+'X'
$$
where $(p_1,s_1)$ are the quark momenta and spin. $q_2$ is the gluon momenta. $X$ is ...
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Examples of non-scalar and non-vector waves
Are there any simple examples of non-scalar and non-vector waves, except for gravitational waves? I'm looking for an example in which the wave has more than three independent polarizations.
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LED TE and TM polarization
I’m having some difficulty understanding the concept of polarization in UV LEDs. To summarize the literature, for UV LEDs emitting at longer wavelengths the light they emit is mostly TE polarized, ...
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Are Stokes parameters Lorentz invariant?
Are the Stokes parameters for polarization relativistic? i.e. Lorentz invariant? And if it is so, then how to show it?
