Second harmonic generation of hollow Bessel beams

摘要

A vortical structure of second harmonic (SH) field excited in quadratic nonlinear medium by combined beam composed of two hollow Bessel beams (Bessel vortices) of fundamental frequency (FF) is analyzed. An emergence of the pairs of single-charged vortices in SH beam caused by interaction of Bessel vortices is revealed. Experimentally, splitting of frequency-doubled Bessel vortex of topological charge 2m (m=l,2) into 2m single-charged vortices was observed.