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arXiv · quant-ph/0408017

Angular momentum and the geometrical gauge of localized photon staes

Margaret Hawton·William E. Baylis
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Abstract

Localized photon states have non-zero angular momentum that varies with the non-unique choice of a transverse basis and is changed by gauge transformations of the geometric vector potential $\mathbf{a}$. The position operator must depend on the choice of gauge, but a complete gauge transformation of a physically distinct state has no observable effects. The potential $\mathbf{a}$ has a Dirac string singularity that is related to an optical vortex of the electric field.

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Margaret Hawton, William E. Baylis. 2004-08-03. Angular momentum and the geometrical gauge of localized photon staes. https://doi.org/10.1103/physreva.71.033816

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