Twin Spotlight Beam Generation in Quadratic Crystals

TL;DR

This paper demonstrates the experimental creation of twin, localized, two-dimensional light beams at fundamental and second-harmonic frequencies in a quadratic crystal, revealing new insights into multidimensional extreme wave phenomena.

Contribution

It presents the first experimental observation of spontaneous twin beam formation in quadratic nonlinear crystals, a novel phenomenon in multidimensional wave dynamics.

Findings

Twin localized beams form spontaneously from a broad background.

The twin beams appear at fundamental and second-harmonic frequencies.

The beams disappear as laser intensity increases.

Abstract

Optical rogue waves have been extensively studied in the past two decades. However, observations of multidimensional extreme wave events remain surprisingly scarce. In this work we present the experimental demonstration of the spontaneous generation of spatially localized two-dimensional beams in a quadratic nonlinear crystal, which are composed by twin components at the fundamental and the second-harmonic frequencies. These localized spots of light emerge from a wide background beam, and eventually disappear as the laser beam intensity is progressively increased.