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Transverse rotation of the momentary field distribution and the orbital angular momentum of a light beam

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 نشر من قبل Aleksandr Bekshaev
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف A.Ya. Bekshaev




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The transverse beam pattern, usually observed in experiment, is a result of averaging the optical-frequency oscillations of the electromagnetic field distributed over the beam cross section. An analytical criterion is derived that these oscillations are coupled with a sort of rotation around the beam axis. This criterion appears to be in direct relation with the usual definition of the beam orbital angular momentum.

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