05. Polarization (Jones vectors and matrices, partial polarization, Stokes parameters)
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- čas přidán 28. 08. 2024
- Lecture notes: drive.google.c...
TYPO: at 21:49, I switched e^{i phi} and e^{-i phi} in the off-diagonal elements.
0:42 Vectorial wave equation and polarization
1:40 Jones vector and polarization states
4:54 Jones matrices, polarizers
5:29 Wave plates
9:51 Rotated wave plates or polarizers
13:54 Unpolarized and partially polarized light
14:42 Comparison between partial coherence and partial polarization
16:09 Coherency matrix
17:26 Examples of coherency matrices
18:43 Decomposing the coherency matrix, Stokes parameters
19:54 Defining the Stokes parameters experimentally
21:21 Poincare sphere
23:17 Comparison between polarization states and two-level quantum states
24:23 Interference of polarized fields: Fresnel-Arago laws
Other sources:
Optics: Half-wave plate | MIT Video Demonstrations in Lasers and Optics
• Optics: Half-wave plat...
Optics: Quarter-wave plate | MIT Video Demonstrations in Lasers and Optics
• Optics: Quarter-wave p...
Statistical Optics, Joseph W. Goodman
Hecht, Eugene. "Note on an operational definition of the Stokes parameters." American Journal of Physics 38.9 (1970): 1156-1158
You have done a better job than most of the professors in the graduate school in explaining these concepts. looking forward to more videos.
Thanks a lot, it's tons of information just in 25 minutes!
Thank you very much. For me it was more educational than MIT video about it !!!
Surely quality over quantity. Carry on ur work. Doing great
Thank you for this video.Helped clear a lot of concepts on the confusing topic i.e. polarization of light
Thank you so much for the clear explanation sander.
amazing
thanks
@ 15:12 "Correlation between fields". He meant to say between field-values U and U* (not between field-fluctuations).
Thanks a lot for the clear presentation 😍
Beautiful explanation.
Incredible. Thank you.
Please make a detailed video on mueller matrices , i liked this explanation a lot, thanks !!!
It looks like Jones vectors are mathematically equivalent to Pauli spinors from non-relativistic QM, and the matrices for the Stokes parameters are the Pauli matrices. The Poincare Sphere looks just like the Bloch Sphere. Also, the polarization filters at 21:00 look like projector operators in the Clifford algebra Cl(3). Do you have any idea why these similarities arise?
EDIT: silly me made this comment still with 1 minute in the video left where you bring up these facts. Still, I'm not sure why the the analogies exist?
The analogies are interesting indeed. In fact, it was because I found the explanations of partial polarization lacking, that I turned to explanations about qubit decoherence, because the Poincare sphere and Bloch sphere looked equivalent to me. Then I tried to copy those explanations for qubits and apply them to optical polarization.
I think many analogies between classical optics and quantum mechanics exist because quantum mechanics is basically all about matter having a wave nature, and optics is all about (electromagnetic) waves. I tried to lay out the analogies between quantum mechanics and classical optics that I could think of in this video: czcams.com/video/29Kd85AdZeE/video.html .
Can you post more videos and some with more basics that build up to more complex concepts. You are the only video I can find on this stuff.
I can't guarantee anything due to time constraints, but I very much would like to know what topics you'd like to see more about specifically. How basic do you want to start, and how complex do you want to go?
Well to be honest you went kind of fast. I find myself having to constantly rewind the the clip. There aren't really any videos on this material with Jones Matrix, Mueller Calculus, Jones Calculus, Stokes Vector etc. It would also be nice to have simulation demonstrations. Also maybe incorporate Mie scattering scenarios, and/or applications to biomedical optics. I have taken electromagnetics but none of this was covered. I am doing summer research and we are running Monte Carlo simulations and the output files are are in relation to stokes vector i.e. HI, HV, HQ, HU DAT files. It would help me how to interpret and analyze the data.
Material for undergraduates in optics, and biomedical optics. Optical Properties calculations, Optical Properties simulations, etc. Something that would help someone with no optics experience get a jump start on optics research that they can build on. Translational applications for research scenarios. Phase scattering functions, azimuth scattering dependence. MatLab examples. Diffuse Reflectance Profile analysis.
Please incorporate Monte Carlo ray tracing simulations. Also your English is much better than many of the videos I have seen on this stuff.
I have googled your name, where are you from?
Thanks for the helpful feedback and suggestions. I'm from the Netherlands.
You are making the world a better place by helping aspiring undergraduates learn this field at a much faster rate. You are addressing an critical unmet area.
That was 🎉
Thank you so much.
Creo que lo vendré a ver un par de veces XD
That's a great video
18:56 Is S₃ supposed to have the signs reversed? It looks like it is supposed to be the Pauli Y matrix. EDIT: I should have watched to the end. I see you are already aware of the Pauli matrices.
i want to know what is the matrix elements if i wish to represent linear polarised electric field at an angle 'theta' to x-axis? i was using the coordinates as (1, 0, 0) when the polarised field is in x-direction. Now i want the field be at an angle 'theta' to x-axis. then how this coordinates be? will it be (Cos(theta), 0, 0)?
Sir, this is incredibly useful. Thank you so much!
Nice. I liked this video.
Shouldn't the rotation matrix have the negative sin in the upper right corner?
If you rotate a vector counter-clockwise by theta, then the sine in the upper right corner should have a minus sign. However, at 12:14 (which I assume you're referring to), we don't rotate the vector counter-clockwise, but we rotate the coordinate system counter-clockwise. To describe the same vector in the new coordinate system, it is as if we've rotated the vector clockwise, so the sine in the bottom left should have the minus sign. This is also the reason why at 13:28 we have a R_{-theta} on the right.
Imagine for example a vector pointing in the x direction. If you then rotate the coordinate system by 90 degrees counter-clockwise, the vector now points in the negative y-direction. In order to achieve this, the sine in the bottom left of the rotation matrix should have a minus sign.
Sander Konijnenberg Ah so. Thank you!
And why do you use a Poincare sphere and not a 4-dimensional Stokes cone?
I assume you propose a 4-dimensional cone because the Stokes vector is 4-dimensional? Only 3 of the 4 entries of the Stokes vector define the polarization state. The other entry describes the intensity of the light. But making the light brighter or dimmer is of little interest if we want to describe the state of polarization.
@@SanderKonijnenberg Hello from Russia
Well no. In the scientific literature, it is called the Stokes cone. So the 4-dimensional Stokes cone is an alternative to the Poincare sphere. These
cones describe both fully and partially polarized light. And the degree of polarization (DOP) is the tangent of the half angle of the solution of the Stokes cone.
Remember Albert Einstein's light cone equation?
So the equations are similar.
@@alexAlex-ci9zd Thanks for the explanation. I must confess that I'm unfamiliar with the concept. When I compare the Google search results of 'Stokes cone' to those of 'Poincare sphere', the impression I get is that the Stokes cone is a relatively obscure object. Do you happen to have any references which elaborate more on its applications?
@@SanderKonijnenberg I have a Russian-language link here it is
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Konovalov N.V. Polarizing matrices corresponding to transformations in the Stokes cone: Prepr. / M.V. Keldysh Institute of Applied Mathematics (Moscow), 1985. - 24
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Of course there is a purely mathematical approach
But I have also met an English-speaking one. You can get this Stokes cone yourself using the expression for the degree of polarization of light. It's a pity that you can't show pictures here. We are engaged in active polarizing photography and calculate the Stokes parameters for each pixel on the camera sensor. People's faces skin injuries tattoos, etc.
please how to download the PPT of this video?
I've uploaded it here: drive.google.com/file/d/1fwib186T7INA7NkvN6UzvuMGfQN8puVA/view
Everyone better watch this video in 0.75 playback speed. He talks so fast
True, I was rather unexperienced in making video presentations back then (everyone has to start somewhere). Not sure if I'm adequately experienced now. I hope you understand, and that this video was at least somewhat useful nonetheless.
@@SanderKonijnenberg I understand and appreciate your effort. The video helped me. It was just a suggestion for the viewers because I watched it twice. Thanks again