Polarization Vectors: Momentum & Helicity Explained

[emma83]

Can somebody explain me what are precisely the polarization vectors of a photon and how they relate to the photon's momentum and helicity ?

Or give me reference of textbooks in which I could learn more on this topic ?

Thanks a lot for your help!

 

[samalkhaiat]

Hi,

see post #5 in

www.physicsforums.com/showthread.php?t=252102


regards

sam

 

[Meir Achuz]

Can somebody explain me what are precisely the polarization vectors of a photon and how they relate to the photon's momentum and helicity ?

The simple description is that a photon can be left or right circularly polarized. A left polarized photon has helicity +1 and a right polarized photon has helicity -1. The reason for left being associated with + helicity is that circular polarization in optics is defined by looking at the oncoming light, while the helicity is the spin angular momentum in the direction of the photons momentum.