We report what is believed to be the first experimental demonstration of so
liton content as a function of the intensity of input light for multicolor
quadratic solitons. Experiments were conducted with spatial solitons excite
d with Gaussian beams in a bulk crystal cut for second-harmonic generation.
The effects introduced by the finite crystal length and by the scheme empl
oyed to elucidate the soliton energy are highlighted. (C) 2001 Optical Soci
ety of America.