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Photon localization barrier can be overcome

P. Saari·M. Menert·H. Valtna
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Abstract

In contradistinction to a widespread belief that the spatial localization of photons is restricted by a power-law falloff of the photon energy density, I.Bialynicki-Birula [Phys. Rev. Lett. 80, 5247 (1998)] has proved that any stronger -- up to an almost exponential -- falloff is allowed. We are showing that for certain specifically designed cylindrical one-photon states the localization is even better in lateral directions. If the photon state is built from the so-called focus wave mode, the falloff in the waist cross-section plane turns out to be quadratically exponential (Gaussian) and such strong localization persists in the course of propagation.

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P. Saari, M. Menert, H. Valtna. 2004-09-06. Photon localization barrier can be overcome. https://doi.org/10.1016/j.optcom.2004.11.020

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