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A Quantum Field Theory Twist to Photon Angular Momentum

G. F. Calvo·A. Picon·E. Bagan
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Abstract

A quantum field theory approach is put forward to generalize the concept of classical spatial light beams carrying orbital angular momentum to the single-photon level. This quantization framework is carried out both in the paraxial and nonparaxial regimes. Upon extension to the optical phase space, closed-form expressions are found for a photon Wigner representation describing transformations on the orbital Poincare sphere of unitarily related families of paraxial spatial modes.

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G. F. Calvo, A. Picon, E. Bagan. 2005-09-06. A Quantum Field Theory Twist to Photon Angular Momentum. https://arxiv.org/abs/quant-ph/0509040

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