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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What parameters descibe a gravitational wave?
What are the parameters of gravitational waves and how does the configuration of the system that creates those waves affect the result?
My current state of missunderstanding is:
Frequency (due to ...
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Propagation of vectorial electric field with Fourier Optics
In Fourier Optics one can propagate in free space the electric field $E(x,y)$ of a monochromatic light beam along the z-axis by decomposing it into plane waves via the Fourier transform, then ...
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Unphysical gauge boson polarizations in non-abelian gauge theory
I am learning P&S's chapter 16 , quantization of non-abelian gauge theory.(all my ref. formula in this post lie in P&S's book) I am puzzled for the logic of the unphysical polarization of ...
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How can we interpret polarization and frequency when we are dealing with one single photon?
If polarization is interpreted as a pattern/direction of the electric-field in an electromagnetic wave and the frequency as the frequency of oscillation, how can we interpret polarization and ...
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Far field horizontal polarization component of a dipole antenna
An infinitely thin dipole radiates an electromagnetic wave which in the far field is vertically polarized, with zero horizontally polarized component. I am trying to understand what happens when the ...
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Spinor-helicity variables and gauge transformations of the polarization vector
I am reading Clifford Cheung's 2017 TASI Lectures on Scattering Amplitudes. In section 2, "Crash Course in Kinematics", the spinor-helicity variables are introduced and discussed. In terms ...
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Physical meaning of polarization
What do we mean when we say an electromagnetic radiation/photons can be polarized in a physical sense? If it means orienting the light along certain axes or 'poles', do these poles have any real world ...
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Doubts concerning Wigner's classification
Wigner classified particles in function of the eigenvalues of $P_\mu P^\mu$ and $W_\mu W^\mu$. Then, it can be proved that for massless particles spin values can be only $\pm s_{max}$. But for a ...
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Why massless particles have less number of possible polarisations than massive ones? [duplicate]
It is stated that according to quantum field theory the value $0$ for the projection of the spin of the photon would be impossible because the photon has null mass, thus photon has two polarizations ...
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Pockels Cell reverse propagation
Pockels Cells are called "voltage controlled waveplates", since the voltage changes the birefringence of the material, leading to the same birefringence induced change of total polarisation plane than ...
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Soft bremsstrahlung calculation in Peskin and Schreoder
On page 183 of Peskin and Schroeder, we have the following scattering cross section
$$\tag{6.23}d\sigma(p\rightarrow p'+\gamma)=d\sigma(p\rightarrow p')\cdot \int\,\frac{d^3k}{(2\pi)^3}\frac{1}{2k}\...
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Can anyone tell How to write the Real and Imaginary parts of Circular polarisation in terms of Unit vector components?
In my computational simulations, i want to mention the 'real' and 'imaginary' parts of 'Circular' and 'Elliptical' polarised light as an input. Now the syntax of that input is such that i have to give ...
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Why is reflected light polarised?
Why is reflected light polarised?
I have learnt about Brewster's angle, and how at a particular angle all light reflected is polarised, but do not understand why. Is this something that could be ...
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Is a rope the correct analogy for light to understand what polarization is?
I want to understand the essence of the CHSH experiment, and for this I need to understand what the polarization of light is. When light passes through a polarizer, a slightly mysterious process ...
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Double slit experiment with one circular polarizer in front of only one slit in the which-way perspective?
If one puts in front of a double slit two quarter-wave circular polarizers (QWP) in front of each slit, say one with 45° and the other with -45° orientation (fast and slow axis - i.e. clock- and anti-...
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Electrolyte capacitor polarization
The anode of the electrolyte capacitor is an aluminum with an aluminum oxide. The cathode is also aluminum separated by electrolyte liquid.
As far as I understand the dielectric is formed at the anode ...
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Does natural/unpolarized light have a well defined classical electromagnetic field?
The typical model for unpolarized light consists of two linearly polarized waves at right angles to each other, where the phase difference changes randomly every so often. Instead of two linear ...
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What are the polarizations of an entangled photon pair?
My understanding of polarization of light is that a photon can be horizontally polarized, or vertically polarized, or some angle in between (eg 45 degrees from horizontal) — leaving aside circularly ...
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Most polarizable solid under standard conditions?
I'm trying to figure out what the most polarizable solid that can be used at standard conditions is.
Wikipedia says alkanes are the most polarizable materials: https://en.wikipedia.org/wiki/...
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Why Do Polarizers Make The Sky Bluer and The Trees Greener?
I've been reading a lot about polarization and I have pretty much understood the physics behind the phenomenon. However, until now I couldn't find a scientific reference that explains clearly why the ...
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Rotation of the image formed by the extraordinary ray upon rotating the calcite crystal
Let a black spot is drawn on a piece of white paper. If we place a transparent calcite crystal on top of the paper, we observe two non-coincident images of the black spot. This is due to the ...
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For which of the candidate gravitation theories has LIGO been able to establish a 5 sigma exclusion of gravitational wave polarization predictions?
In "Gravitational Wave Polarizations: A test of General Relativity using Binary Black hole mergers" the candidate gravitation theories and their gravitational wave polarizations are given in ...
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Recognizing linear or polarized light and seeing its direction
I watched Walter Lewin's course, and he said he learned how to see and recognize polarized or linear light. And I wonder what it might be. What are the tricks?
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Is the direct definition of relative permittivity the same as that obtained by electric susceptibility?
First of all, the direct definition of relative permittivity $\epsilon_r$ is obtained by the ratio of absolute permittivity $\varepsilon$ to vacuum permittivity$\varepsilon_0$:
$$
\epsilon_r = \dfrac{\...
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Exotic types of polarization
I am aware that in the classical approximation of electromagnetic waves, waves can be linearly polarized (so that the B-field oscillates in one dimension as $B=B_0\cos(\omega t)$), circularly ...
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Electric susceptibility in matter $E(t)= E_0 \delta(t-t_0)$
I have few questions about the Electric susceptibility in matter.
First of all, the example begins with $E(t)= E_0 \delta(t-t_0)$.
I'm not sure what does it means. My guess is that the electric field ...
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Which experiment can differentiate a statistical mixture from a superposition state?
I am in trouble with polarization and entanglement.
Let's consider three cases :
Case 1) : Statistical mixture of $|H\rangle$ and $|V\rangle$ polarized photons
Case 2) : Photons in a superposition ...
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Why is fresh asphalt polarized?
I noticed when riding my bicycle with some polarized sunglasses that a fresh coat of asphalt appears polarized (ie. when I tilted my head, I saw it as lighter and darker, as when viewing a polarized ...
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Electric fields affecting recombination of virtual particle pairs
Besides the Schwinger effect, whereby a strong enough electric field can cause the creation of virtual particle pairs in the quantum vacuum, I have also read that a suitable electric field is able to ...
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Is it possible to make multiple monitors (with glasses) in a way that each of the glasses would be able to see their specific monitor but not others?
So i was interested if i could make A B C monitors lets say and ive a b c glasses for all of them. My question was that is it physicly possible to make 3 same screens in a way that when i put on a ...
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Is photon spin and polarization the same thing?
I have posted here regarding this before. I always get conflicting information when I research about this stuff.
Some people say that a photon spins in or against it’s direction of motion…meaning if ...
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What is photon spin and polarization?
I have literally googled for hours on this subject. I am very curious on what spin really is and how polarization works for photons.
I’ve read that photons have a spin of 1(no idea what that means or ...
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Polarisation definition
What is more correct and what is the difference?
Polarised waves are waves with vibrations in one direction perpendicular to energy propagation
"vibrations in one plane"
"vibrations in one direction ...
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What is exactly the electric displacement?
I found a lot of definitions of the electric displacement and none of them made sense to me, some say it's the electric field in the dielectric, some say it's the density of free charges and some say ...
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Phase shifts introduced by a beam splitter
I am studying this paper about the automatic generation of quantum experiments. The algorithm they are using is based on a series of symbolic transformations that are used to simulate the effects of ...
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Difference between Poincaré and Bloch sphere for single photons
The Bloch sphere is a geometrical representation of a two-levels quantum system, for example we can use it to represent the spin of a single qubit in the basis $\{\lvert H \rangle, \lvert V \rangle\}$....
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Polarization of conduction and valence bands
As title, this is something that I read in the paper "Quantitative relationship between polarization differences and the zone averaged shift photocurrent" (PRB 96, 075421 (2017)).
This paper ...
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If the photon hasn't an electric and magnetic field yet, then what does its polarization vector stand for?
In the context of quantum electrodynamics, The photon field is described by a operators connected to a Fock space of photon states $e^{-ip_{\mu}x^{\mu}}$.
The relativistic photon wavefunction can be ...
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Using beamsplitters for co-axial light paths
Good afternoon all,
I have been racking my 'optics novice' brain on how to use the same optical path for both the transmit and receive optics for a simple laser range finder. For simplicity in the ...
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Can a single photon have circular polarization?
There are on this site a few questions about photons and circular polarization, but none of them give satisfactory answers:
Connection between spin angular momentum of a photon and circular ...
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What's the equivalent of the polarization vector of photons for gravitons?
Spin-0, spin-1/2, and spin-1 particles have an associated quality expressing the spin structure of the field.
Spin-0 fields obviously have no extra quality. Spin-1/2 fields are expressed by spinors ...
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$\pi, ~\sigma$ - atomic transitions with respect to a quantization axis
In the absence of a magnetic field, how does one physically (i.e. perhaps in a thought expt) access $\Delta m = 0 ~~\textrm{or}~~ \pm1$ transitions since (as I understand it) the choice of ...
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Three polarizers, 45° apart
If light is passed through two polarizing filters before arriving at a target, and both of the filters are oriented at 90° to each other, then no light will be received at the target. If a third ...
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How to disentangle two entagled particles (photons) without distroying anyone?
Can a twin photon pair entagled in polarization get disentangled after one of the photons meets a PBS (polarization beam splitter). I suppose after the PBS the photon will go one way or another ...
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Does Gyrator change phase of wave?
I have read that gyrator changes direction of polarization of linearly polarized wave. But then it is also given that phase is also changed. How are two related? I understand due to faraday rotation ...
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Do EM waves cancel out permanently in this example?
If we emit two photon rays one from each source 1 and 2 and after they reflect on mirrors to reach the same trajectory they should cancel out in the case their phases are opposite 100% but will any EM ...
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What are the speeds of light inside a retarder?
A retarder introduces a phase shift between the field components traveling along the fast axis and the slow axis. But at what speeds are they actually traveling? Is the speed of light along the fast ...
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Polarizing axis of the polarizer
As I know, a linear polarizer is a transparent optical instrument (like a piece of glass) that has a polarizing axis. Electric field components of electromagnetic waves that are parallel to polarizing ...
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Why does the graviton polarization satisfy $\epsilon_{ij}(\mathbf{k},\lambda)\epsilon^{ij}(\mathbf{k},\lambda') = 2 \delta_{\lambda\lambda'}$?
I am reading the paper ``Graviton Mode Function in Inflationary Cosmology'' by Ng (link here). The graviton $h_{ij}$ is here expanded (in the TT gauge) where
$$
h_{ij}(x) \sim \epsilon_{ij}(\mathbf{k},...
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Is specific rotation a constant? [closed]
This is the formula for Specific Rotation of a solution.
Can I rearrange to make c as the subject and then say that theta is proportional to c?
If not, is there any other way in which I could relate ...
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