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arXiv · 1904.08122

Reexamination of energy flow velocities of non-diffracting localized waves

Peeter Saari·Ott Rebane·Ioannis Besieris
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Abstract

A universal relation has been established between the local energy transport velocity along the direction of propagation and the group velocity of scalar and vector-valued propagation-invariant spatiotemporally localized superluminal and subluminal electromagnetic waves in free space. Under specific restrictions, this relationship is very closely valid for physically realizable almost propagation-invariant spatiotemporally confined subluminal and superluminal electromagnetic fields. In both cases, although the group velocity may be either superluminal or subluminal, the universal relation is in accord with the well-established result that the upper limit of the energy transport velocity is c, the speed of light in vacuum.

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Peeter Saari, Ott Rebane, Ioannis Besieris. 2019-04-17. Reexamination of energy flow velocities of non-diffracting localized waves. https://doi.org/10.1103/physreva.100.013849

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