Polarization Definition and 613 Threads

Homework Statement Write an expression for a light wave circular polarized to the right, traveling in the positive ZZ direction, such that the electric field points in the negative XX direction at z=0, t=0.Homework Equations Right handed polarization is the same as clockwise, I think...

Hi, I'm new to this forum, and I need some help with this. I want to determine the polarization of a laser beam, that is, the type of polarization (linear, elliptical), the angle of polarization (if it is linear). Then, I want to represent this mathematically. I used some linear polarizers to...

Two entangled photons from a same-polarization source have their polarization measured at 120 deg difference from each other. If I understood right all the simplified Bell-theorem and Bell-test explanations out there, QM and experiments say the chance for coincidence will be 25% no matter which...

Hi all, I'm implementing a computer vision system with a near-infrared laser and a NIR bandpass filter. It shines a laser on things and looks for a reflection. I'm getting a bunch of interference from sunlight and was thinking of using a polarizing filter to cut some of the sunlight out...

Homework Statement Homework Equations The Attempt at a Solution I know that according to the Malus law formula, if the angle is 0 < θ < 90 then there is some transmission. But I need help understanding this physically. If we think of a polarizer/analyzer as a "lattice", i.e. kind of like...

I read that if a beam of unpolarized light goes through a polarizer, the intensity of the polarized beam is equal to half the intensity of the original beam. Can someone explain me why? I thought the intensity would be the same.

Homework Statement Unpolarized light of intensity Io is incident on two polarizing sheets whose axes are perpendicular. A) what is the intensity of the light after the first sheet? B) what is the intensity of the light after the second sheet? Homework Equations I=(Imax)cos^2(Θ) The Attempt...

Hi, I'm trying to understand particle polarization. To my understanding if a particle is in a pure quantum state with non-zero spin (i.e. spin up) then it is fully polarized. If it is in a superposition of different spin states then it is weakly polarized and if its properties are uniform...

A simple question: is the polarization of light affected in any way upon reflection? What about upon refraction/diffraction? What interactions affect polarization?

So I know how polaroids and 0.5λ plates work, but does this mean that the polarization of the light and the phase of light are the same, but that the polarization of light is actually a vector description of light? Or something like that? Are these two the same?

Homework Statement Part (a): Explain how birefringence adds phase difference. Part(b): Explain how the concept of birefringence is used in a beam splitter. Part (c): What's the orientation and retardance of retarder-1 to make both beams have same intensity? Part (d): What's the...

Homework Statement Find the angle ϕ between the filter's polarizing axis and the direction of polarization of light necessary to increase the ratio of the clouds' intensity to that of the blue sky so that it is three times the normal value. Express your answer in degrees to four significant...

The data points of the polarization of the CMB are a magnitude and an orientation that varies between 0° and 180°. What kind of mathematical field is that, not quite a vector field? Thanks for any help!

Describe the state of polarization represented by (here w = omega and TT = pi) a) Ex = Esin(kz - wt) & Ey = Ecos(kz - wt) b) Ex = Ecos(kz - wt) & Ey = Ecos(kz - wt + TT/4) c) Ex = Esin(kz - wt) & Ey = Esin(kz - wt)

This is a problem from Boyd Nonlinear Optics chptr 1 problem 2. Homework Statement Numerical estimate of nonlinear optical quantities. A laser beam of frequency ω carrying 1 W of power is focused to a spot size of 30μm diameter in a crystal having a refractive index of n =2 and a second order...

Is light wave always linearly polarized?

Hi, as I understand it, in hydrogen with its electron in the p-orbital there is a charge polarization (negative in the direction of the dumb-bell orbitals, positive in the other directions). Is this also the case for positronium in the p-orbital state ? I'd guess there cannot be any...

I have a disagreement with a Quantum mechanical scientist about a double slit experiment with polarizers, which gives interference or not depending on "which path" knowledge of the photon. That is alright with me, but I can calculate the same results with classical wave formula. He does not...

Hi, i have a question about the center of mass change during photon emission in terms of the polarization of the emitted photon. first, a few facts are as follows: i) selection rule: if delta m=0, that means p (atomic recoil) = p (photon) in magnitude. This is of pi transition and...

Hello i wasn't sure if to ask this in here or in homework! I stumbled upon an assignment to build the model of photon gas in 2D space. in the answer it was stated that the light have 2 polarization states in 2D model, how come? the field have only one way to propagate regarding the wave...

Hello all! My friend and I are having a bit of a discussion. We did an experiment on liquid crystals as dielectrics with changing voltage, and we came across some weird conclusions (capacitance decreased with increasing voltage? odd. Our theory is that liquid crystals don't act as normal...

Hi there all, I am a little confused about polarization. If I have a laser beam incident on a single polariser, if I adjust the angle of the polarizers transmission axis so that it is aligned with the plane of polarization of the incident laser beam does it intensity remain unchanged, or does...

Suppose we consider a proton where we set the electric charge of the three quarks towards zero. At this point I assume we still would have the three quarks bound together? Now reduce the strength of the strong force by say ten times. I was told in posts that the radius of the proton depends on...

Homework Statement Hey guys. I have an electromagnetic wave traveling in the z direction and polarized in the x direction. The frequency is 1 MHz and average power density is 1 W/m^2. An antenna in the shape of a circular wire is in the xy-plane centred at the origin. I would like to use...

Hello everybody :) I'm doing some electromagnetic exercises, but I got stuck in calculating the polarization of a plane wave. The complex field associated to the wave is the following \vec{E} = (\sqrt{2}\hat{x}+\hat{y}-\hat{z})e^{-2\pi 10^6(y+z)} = \hat{p}e^{-2\pi 10^6(y+z)} It is easy to...

Why do polarization mechanisms decrease with frequency in the following order: Space charge/Interface Dipole Ionic Electronic See page 3 in the attached document for reference. Edit: corrected error in wording

Maxwell-Wagner polarization is generally described in literature as the polarization of interfaces, such as grain boundaries, with an applied electric field. In the Wikipedia article (http://en.wikipedia.org/wiki/Maxwell–Wagner–Sillars_polarization), it's mentioned that "the charges are often...

Homework Statement Determine the state of polarization of the following wave and its azimuthal angle: ##E= \sqrt{3} E_0 \cos(kz-\omega t) \hat{x} + E_0 \cos(kz- \omega t + \pi) \hat{y}## The Attempt at a Solution How do I calculate the azimuthal angle? :confused: My textbook only says...

If you have played around with polarizers you might have noticed that flipping a polarizer by 180o about the vertical axis has the same result as rotating it by 90o about the horizontal axis[i.e. flipping so that the face of the polarizer which was facing away now faces you has the same effect...

Hi, I'm sorry this is a silly question. My basic understanding of EMR is that it is an oscillating electric field perpendicular to an oscillating magnetic field, and my basic understand of polarization is that it let's either horizontally or vertically oriented EMR through. How can that be if...

Hi all! In Ruth Durrer's book "The Cosmic Microwave Background" there is this picture (Fig. 5.2 page 193) about the E and B mode of the CMB polarization: http://imageshack.us/photo/my-images/11/s7o6.png/ http://imageshack.us/photo/my-images/11/s7o6.png/ They represent the E and B...

I have a vertically linear polarized laser according to specs. "Polarization ratio 100:1; Vertical linear polarization". However, When I place a polarizer in front of the laser its maximum is at 132 deg. and minimum is at 42deg. Thats 90 degrees apart.. Placing two polariazer infront of...

Homework Statement A sphere of radius R carries a polarization of \vec{P} = k \vec{r}, where k is a constant and \vec{r} is the vector from the center. Find the bopund charges, and the field inside and outside the sphere Homework Equations - \nabla \cdot \vec{P} \sigma _b = \vec{P} \cdot...

I've been reading Griffith's "Introduction to Electrodynamics" and I've got to this part where it says: "When you are asked to compute the electric displacement, first look for symmetry. If the problem exhibits spherical, cylindrical, or plane symmetry, then you can get \vec{D}directly from...

Homework Statement A beam of unpolarized light is incident on a series of three polarizers as shown. The angle of the transmission axis of each polarizer is indicated by the dashed line, with q1 = 110, q2 =230, and q3 = 370 (all defined relative to vertical). What is the ratio of the...

Homework Statement In order to decrease the intensity of a beam of unpolarized light to 10% of its original intensity using two polarizers, what is the required value of θ, the angle between the transmission axes of the two polarizers? Homework Equations tanθB=n2/n1 The...

A single photon approaches a polarization filter. It's orientation is described by a probability amplitude wave function. It is not reflected or absorbed, but passes through the filter. Now it's orientation immediately after is definitely known. Question 1: is there no...

When a photon is produced when an atom raised to excited state return to ground state it's frequency can be calculated. but can we predict the direction and polarization of that photon.

Hi all, Imagine a double slit experiment where each slit contains a polarization filter with some angle relative to each other (\alpha). If the polarization filters are parallel the usual interference pattern will emerge, and when they are perpendicular no interference pattern will emerge. What...

Hello all, I've been reading up on both potential and current polarization for directional phase relays in, "Power System Relaying" by Stanley H. Horowitz and Arun G. Phadke and I am confused as to how the direction of the fault (i.e. into or out of the line) is obtained. In potential...

I'm studying wave interference and having trouble to understand some concepts. I would like to ask what would happen in the 2 situations below Image 1 Image 2 Both waves are identical, have the same frequency, amplitude and velocity. They are polarized on the direction shown (first...

I read that for a plane wave E, B and k are always perpendicular to each other but then in a TM mode I have electric field in the direction of propagation. This means this TM and TE modes I cannot have in free space? Can I have them in a laser? If I can have some E-field in the direction of...

Does the electric polarization density of a dielectric inside a capacitor have the same direction as the electrical field? Considering the electric dipole moment vector goes from the - charge to + charge?

So I know that a linearly polarized photon is in a state ψ = cos(θ)\left|x\right\rangle + sin(θ)\left|y\right\rangle What if θ depends on time maybe something like θ\equiv\frac{E_{0}t}{\hbar}? The polarization is linear at any time t, it rotates as time passes? Isn't that circular...

Homework Statement A beam of light is reflected off the surface of some unknown liquid, and the light is examined with a linear sheet polarizer. It is found that when the central axis of the polarizer (that is, perpendicular to the plane of the sheet) is tilted down from the vertical at an...

¿ Why the photons emitted by an electron are desintegrated in a photon, and then in an electron a positron? The positive charge stay near the electron doing that charge stay minus than its real value. But, ¿ why don´t matter the same with the mass??

I was reading in my QM book that neutrinos are "essentially left handedly polarized." (Townsend on Page 119) If neutrinos can be polarized, what is oscillating? Do other particles with mass exhibit polarization?

Homework Statement A circularly polarized light hit the boundary between 2 regions at 45 degree and is totally reflected. What is the polarization state of the reflected beam? Homework Equations The Attempt at a Solution Since both s and p component are totally reflected...

Homework Statement Three polarizing filters are stacked, with the polarizing axis of the second and third filters at 23.0° and 62.0°, respectively, to that of the first. If unpolarized light is incident on the stack, the light has intensity 75.0 W/cm^2 after it passes through the stack. If...

Hi, I am currently studying quantum field theory with worldwidely used text written by Peskin and Schroeder. On page 165 of that text it says, " the amplitude vanishes unless the final photon is right-handed." But I cannot figure out how it works. With ε = (0,1,i,0), I get same expression...