Observation of concentrating paraxial beams

TL;DR

This paper reports the first experimental observation of concentrating paraxial light beams in a linear nondispersive medium, demonstrating their unique ability to focus strongly while maintaining finite total energy.

Contribution

It provides the first experimental realization of concentrating paraxial beams, confirming theoretical predictions and exploring their unique focusing properties.

Findings

Beams can focus like plane waves in a lens focal spot

Beams maintain finite total energy despite strong focusing

Experimental validation of theoretical predictions

Abstract

We report,to the best of our knowledge, the first observation of concentrating paraxial beams of light in a linear nondispersive medium. We have generated this intriguing class of light beams, recently predicted by one of us, in both one- and two-dimensional configurations. As we demonstrate in our experiments, these concentrating beams display unconventional features, such as the ability to strongly focus in the focal spot of a thin lens like a plane wave, while keeping their total energy finite.