Comment on Half-Integer Quantum Numbers for the Total Angular Momentum of Photons in Light Beams with Finite Lateral Extensions
American Journal of Modern Physics
Volume 6, Issue 5, September 2017, Pages: 88-90
Received: Jul. 5, 2017; Accepted: Jul. 20, 2017; Published: Aug. 15, 2017
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Manfred Fähnle, Max Plank Institute for Intelligent Systems, Stuttgart, Germany
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Recently the spectacular result was derived quantum mechanically that the total angular momentum of photons in light beams with finite lateral extensions can have half-integer quantum numbers. In a circularly polarized Gauss light beam it is half of the spin angular momentum which it would have in a respective infinitely extended wave. In another paper it was shown by a classical calculation that the magnetic moment induced by such a beam in a metal is a factor of two smaller than the one induced by a respective infinitely extended wave. Since the system's angular momentum is proportional to its magnetic moment it could be assumed that the classical result for the magnetic moment reflects the transfer of the total angular momenta of the beam photons to the metal. Here we show that there is no hint that this is indeed the case.
Light Beams with Finite Lateral Extensions, Total Angular Momentum of Photons, Induced Magnetic Moment in Metal
To cite this article
Manfred Fähnle, Comment on Half-Integer Quantum Numbers for the Total Angular Momentum of Photons in Light Beams with Finite Lateral Extensions, American Journal of Modern Physics. Vol. 6, No. 5, 2017, pp. 88-90. doi: 10.11648/j.ajmp.20170605.12
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