Polarization Definition and 666 Threads

I've searched high and low for answers to this, and a friend of mine finally pointed me in the right direction. I decided to write a post about it so hopefully others who have the same question will find the answer more easily. When linearly polarized light is reflected at a 3D angle, the...

Homework Statement We have a crude model for the polarization of a hydrogen atom, by approximating its 1s orbital with a uniformly charged ball of radius a. What is the (negative) charge density of the electron cloud? What is the electric field inside the cloud, at the point with radius vector...

Imagine that one has a single photon of 632nm. It enters the back end of an open-ended HeNe laser tube - one with no mirrors - and along its path, causes the emission of another photon. According to the wikipedia entry on stimulated emission (https://en.wikipedia.org/wiki/Stimulated_emission)...

Hi. We can write a polarised photon as ##\left|\alpha\right\rangle=\cos(\alpha)\left|\updownarrow\right\rangle+\sin(\alpha)\left|\leftrightarrow\right\rangle##. Trigonometry gives us $$\left\langle\alpha | \beta\right\rangle=\cos(\alpha)\cos(\beta)+\sin(\alpha)\sin(\beta)=\cos(\alpha-\beta)$$...

I have several questions about the scattering of light. Air molecules scatter sunlight and makes the sky blue, many books say that the air molecules are oscillated by E field and so they becomes sources of EM wave. Is it because the air molecules have charges? I wonder if air molecules or...

From a textbook I read something like this: "When sunlight is reflected from a horizontal surface, the plane of incidence is vertical, and the reflected light contains a preponderance of light that is polarized in the horizontal direction... The manufacturer makes the polarizing axis of the lens...

What is the best source for understanding the membrane polarization effect in rocks??

What exactly are surface bound charge and body bound charge? Is there any difference between: 1) surface bound charge and surface charge 2) body bound charge and body charge How do we know if surface and body bound charge exist? Does polarized material always have surface and/or body bound...

Dear All: I have recently encountered a small question regarding the determination of the degree of circular polarization of light. In an optical experiment, we are trying to create a circular polarized light beam by passing a HeNe-laser through a linear polarizer and a quarter wave plate (in...

Is this statement correct: ? "The effect of making this observation is to force the photon entirely into the state of parallel or entirely into the state of perpendicular polarization." * I don't see how you can talk about how the polarization of a photon changes if the photon gets absorbed...

Question: We want to rotate the direction of polarization of a beam of light through 90 degrees by sending the beam through one or more polarizing sheets. (a) What is the minimum number of sheets required? (b) What is the minimum number of sheets required if the transmitted intensity is to be...

Homework Statement 2 media whose refractive indices are 1 and n respectively are separated by a flat interface. An EM plane wave goes from medium 1 to medium 2 with a polarization vector making an angle of 45° with the plane of incidence. Determine the incidence angle for which the reflected...

Hello, I am trying to determine how an electromagnetic wave changes polarization upon reflection off of an arbitrary object. Here are my confusions in particular. 1. My assumption is that the change in polarization is very much dependent on the geometry of the object, but I don't know the...

Homework Statement Plate capacitor with distance between plates 'd=4mm' is fully filled with homogeneous linear dielectric. Capacitor is connected to the source of DC voltage, first stationary state is established, then the capacitor is separated from DC voltage source. After that, dielectric...

Let's say I have a linearly polarized laser beam, and I focus it to a small spot using a parabolic mirror. Does the light retain its polarization at the focal point? Why or why not? I understand that flat mirrors and concave/convex mirrors preserve linear polarization, and I would like to make...

Hi, if the laser emits polarized light, then why we use polarizer infront of laser?

Hi all, To me, polarization is the most confusing concepts in optics to me. From the text, it is said that polarization is how the light oriented. A linear polarization means the light is oriented on one direction. But I have few doubts I learn from the book and online materials 1) In most...

The QED theories merely state that a photon has spin and momentum. Are there any reasonable mechanistic descriptions, perhaps in terms of variations of E and H beyond the infinite plane wave (which is also not helpful)?

Homework Statement Hello i am trying to write the Stokes parameters as the amplitude of the averaged EM-wave We know the stokes parameters are {I,M,C,S} or {S0,S1,S2,S3} thus a column vector. And S0 is defined as S0=<E2x0>T+<E2y0>T S0 i understand how it was derived since Filter 0 is an...

So just to clear things up before we start, does vacuum polarization occur randomly, or does it just occur when an electromagnetic field is present? Also, how would vacuum polarization conserve energy - does it take energy from the field or does it emit negative energy gravity waves or...

I'm in need of some help understanding the viewing angle of a basic LCD. I am replicating a product that contains a backlit LCD from a similar product. The original product has an orange display that is clearly viewable at most angles. The similar product has a blue display that has poor...

Homework Statement An infinitely long dielectric cylinder with radius R and relative permittivity ##\epsilon_r## contains a free charge density given by: ##\rho(s)= ks## for s<R and 0 for s>R, where k is a constant. Find the polarization P and any volume or surface polarization charge...

Hi there, In the decay of ## B \to D^* l \nu ##, I found that the polarization vectors are described as following: In the B rest frame the helicity basis ## \bar{\epsilon}(0)= \frac{1}{\sqrt{q^2}} (p_{D^*},0,0,-q_0), \\ \bar{\epsilon}(\pm)=\pm \frac{1}{\sqrt{2}} (0,\pm 1,- i,0), \\...

Homework Statement Elliptically polarized light, where the rotation of the ellipse is ##\pi/6## and its major axis is ##2E_0## and minor axis ##E_0##, is left through a polarization foil. The foil transmits light in ##x## axis (a) and in ##y## axis (b). Calculate the ratio of transmitted light...

In A. Zee "QFT in a nutshell" in chapter I.5 Exercise 1.5.1 on page 39 for spin 2 massive propagator. I know I’m missing something very simple (self-taught beginner). I'm trying to derive equation (13) on page 35, which is G_{\mu\nu,\lambda\sigma} = G_{\mu\lambda}G_{\nu\sigma} +...

I am trying to understand circular polarization and Real 3D glasses.I am sure that answers will lead to other questions. Question 1. Are Real 3D glasses merely quarter wave plates with each eye set at 90 deg angles to the other? or.. Question 2. Do Real 3D glasses consist of a linear...

Hello. What is troubling me is I can't stabilish a connection. and it seems to be it should exist, between the polarization of a material by displacement of the electron cloud and energy level transition in a molecule or solid. When an electric field is applied to a material, the "electronic...

I am looking for a robust text on stress analysis using photoelasticity. Razumovsky's "Interference-Optical Methods of Solid Mechanics" has been the best looking one so far, but with a >£100 price tag with only Chapter 1 (=30 pages) useful to me, I could do with finding an equally robust...

Homework Statement Two polarizing sheets have their transmission axes crossed so that no light gets through. A third sheet is inserted between the first two such that its transmission axis makes an angle θ with that of the first sheet. Unpolarized light of intensity I0 is incident on the first...

Is there any relation between refractive index and polarization?

From what I understand, neurons at rest are in a state of polarization, with Na+ ions abundant on the outside of the cell and K+ ions abundant on the inside of the cell. During depolarization, sodium ions rush in, creating a highly positive charge on the inside of the cell relatively to the...

Hi pf, I am trying to find answers to the following two questions about polarization of light but am struggling to find anything: 1) When unpolarized light strikes the surface of water, some of the reflected light is horizontally polarized. I was trying to find out what causes this to happen...

I know that a linear voice coil is polarized from top to bottom, but how is a flat coil polarized? Would a flat coil be polarized from the inside to the outside? Where the inside(blue) is one pole and the outside(red) is the other? If you were to do multiple windings(stacked layers) would it...

Hi all, I am wondering how is it possible that the polarization effects of a dielectric material remain confined inside the material itself. That is: for a LIH dielectric, the equations state that the electric field inside the material is reduced by \epsilon_r. But outside the material, no...

I read in few places that the virtual photons have longitudinal polarization while in some papers they say virtual photons have both transverse and longitudinal polarizations. Can anyone please help me to understand this

Homework Statement Evaluate the matrix elements ## {\mathbb S}=\left( \begin{array}{cc} \langle x|\mathbb{\hat J}_z|x\rangle& \langle x|\mathbb{\hat J}_z|y\rangle\\ \langle y|\mathbb{\hat J}_z|x\rangle &\langle y|\mathbb{\hat J}_z|y\rangle\end{array}\right)## by expressing the linear...

I finished my online E&M class today, and the prof told us to experiment with polarizers. While doing that, I found this: I put a piece of plastic between two polarizers, and found that at a certain angle between the two polarizers, a portion - though not all - of the plastic darkened. So I...

So I just started Physics 2 Electricity and Magnetism and I'm already scared for my life. The professor first did a demonstration where he charged up a Teflon rod on some sort of cloth and moved an aluminium can with the rod. I understand how that happens. The can is a metal and conductor so the...

I read once (I don't remember exactly where) that X-rays scattered perpendicularly to the direction of the incident X-rays are linearly polarized (even although the incident ones are not). I think the discussion was in the context of low energy X-rays, and the explanation used classical...

Bonnes fetes de Noel. When an excited electron returns to its ground state a photon is emitted. Suppose that the electron's spin skip from +1/2 to -1/2 (around z)and that the photon has a momentum parallel to z. I suppose that this photon has a circular polarization around z (Is it true?) The...

Hi, I'm thinking the following scenario. I have some solution in a container, where polymers are dissolved inside. If left so, the polymer will be homogeneous in the liquids. Now I add an electric field on the two sides of the container, will the polymers be polarized and stretched? So the...

For internal photon states, is it necessary to sum over the longitudinal polarization state in addition to the transverse states? And if so, does the ordinary Feynman-gauge propagator take care of this? Thanks!

http://www.iflscience.com/physics/physicists-develop-reversible-laser-tractor-beam-functional-over-long-distances In this article, they said they could control the particle's direction by changing the laser's polarization. Could someone explain this to me? I have to do a presentation on it...

Hello, Given an electromagnetic wave that is, from a classical point-of-view, not circular polarized. Does that correspond in QM to photons with the ZERO spin eigenstate? Thanks in advance.

Homework Statement Hi! The entire problem is this: (a) Two plane-polarized harmonic plane waves having the same propagation constant are polarized, respectively, along two perpendicular directions. Show that if the phases of the two waves are different, their superposition yields generally an...

Hello, I hope I got the section right ;). I orginally posted this in the physics section, but as the problem is more mathematical. It would be nice if someone knows the right direction. I've stumbled upon a math problem while going through some physics and got stuck with some mathematical...

Ok, so I keep reading about these concepts and every source says something different. Even within the same textbook, it says conflicting things. So you have a circularly polarized light that is coming TOWARDS you. That is considered left-circularly polarized or right-circularly polarized? I've...

i have the following questions: Bell inequalities use spin 1/2 matrices and experiments use photons. Is then the electric field horizontal or vertical after the measurement with a polarizer in other words can we assimilate the orientation of the field with a vector in the hilbert space ? How...

Hi, I understand that the α in the form below refers to angle of E-vector to the horizontal. and that a jones vector should be represented this way: I tried to represent the linearly polarized sin & cos form in the jones vector form I know I'm doing something wrong because a linearly...

Who knows where this formula comes? $$ e_i \otimes e_j + e_j \otimes e_i - \frac{2}{3}( \sum_{\substack{k}} e_k \otimes e_k )\delta_{ij} $$