Abstract
A detailed experimental investigation of the spontaneous noncollinear second harmonic generation in biaxial guanylurea(1+) hydrogen phosphite (GUHP) crystal is reported. The number and shape of the resulting second harmonic hollow cones depend explicitly on the direction of propagation of the fundamental beam with respect to the optical axes and the type I or type II phase-matching lines, in agreement with theory and simple calculations.
Spontaneous SHG allows an easy adjustment of the two-beam noncollinear SHG. Due to the large nonlinearity of GUHP, Fabry-Perot enhanced noncollinear SHG has been observed as well.