Register to reply

Orbital angular momentum

by jby
Tags: angular, momentum, orbital
Share this thread:
jcsd
#2
Oct16-03, 07:32 AM
Sci Advisor
PF Gold
P: 2,226
No, I hadn't, I know light has spin angular momentum, but I never realized it had orbital angualr momentum too.
Jonathan
#3
Oct16-03, 08:15 AM
Jonathan's Avatar
P: 493
Yes! I just got that, I had never heard of it before. I'm planning to do as the article says and go get the diffraction grating from that website one of these days. Edit: I just went to the page and see that it doens't have the whole aricle, I just assumed it did...

Tom Mattson
#4
Oct16-03, 04:55 PM
Emeritus
Sci Advisor
PF Gold
Tom Mattson's Avatar
P: 5,532
Orbital angular momentum

The entire article was not available, but here are some info sites on the subject:

http://www.aias.us/pub/OAMLight/oamlight.html

It also has links to 2 research groups.

Here are some articles from the Los Alamos arXiv:

Angular Momentum of Photons Emitted by Atoms
Management of the Orbital Angular Momentum of Light
Photon Orbital Angular Momentum in Astrophysics
bdkeenan00
#5
Oct16-03, 07:18 PM
P: 49
so the photon as linear momentum(P=E/c),spin(intrinsic angular momentum),and now we find out it has orbital angular momentum. Is there any other momenta associated with a photon?

P.S.
What does intrinsic mean anyway?
jcsd
#6
Oct17-03, 06:00 AM
Sci Advisor
PF Gold
P: 2,226
Originally posted by bdkeenan00
so the photon as linear momentum(P=E/c),spin(intrinsic angular momentum),and now we find out it has orbital angular momentum. Is there any other momenta associated with a photon?

P.S.
What does intrinsic mean anyway?
Instrinsic means that it is a fundmanetal property of the photon, i.e. all photons have a spin quantum number(s) of 1 which is related to the spin angular momentum by:

√s(s+1)h/2π

As far as I'm aware, there are no other sorts of angular momentum other than those described associated with the photon (excpet for things like total angualr momentum which is the sum of spin and orbital angular momentum).
eigenguy
#7
Oct17-03, 03:35 PM
P: 97
Where are you guys getting the idea that we didn't know that light has orbital angular momentum?
jcsd
#8
Oct17-03, 07:39 PM
Sci Advisor
PF Gold
P: 2,226
Originally posted by eigenguy
Where are you guys getting the idea that we didn't know that light has orbital angular momentum?
No, it was just that I didn't know light had orbital momentum.
bdkeenan00
#9
Oct19-03, 01:18 PM
P: 49
Originally posted by jcsd
Instrinsic means that it is a fundmanetal property of the photon, i.e. all photons have a spin quantum number(s) of 1 which is related to the spin angular momentum by:

√s(s+1)h/2π

As far as I'm aware, there are no other sorts of angular momentum other than those described associated with the photon (excpet for things like total angualr momentum which is the sum of spin and orbital angular momentum).
Thank you
Swamp Thing
#10
Dec13-03, 01:43 AM
P: 20
The forked grating at http://departments.colgate.edu/physi...s/oamgp/gp.htm

does not seem to have any assymmetry that would decide the direction of twist. What then determines whether the helical wavefront is right or left handed?

[Edit: The Sci Am article referred to in the original post contains a link to the site mentioned here. The page contains a grating pattern that lets anyone create "twisted" light using a laser pointer.]
dlgoff
#11
Dec13-03, 05:53 PM
Sci Advisor
PF Gold
dlgoff's Avatar
P: 2,726
does not seem to have any assymmetry that would decide the direction of twist. What then determines whether the helical wavefront is right or left handed?
quote from paper:
If we calculate the interference pattern generated by combining LG00 and LG0+1...
What would the pattern look like if it is generated with the left handed LG0-1? It must be something like a negative image.


Register to reply

Related Discussions
Electron orbital angular momentum Quantum Physics 7
Orbital and Spin angular momentum Advanced Physics Homework 4
Orbital Angular Momentum Advanced Physics Homework 4
Angular momentum and orbital angular momentum problems Introductory Physics Homework 3