Induced spectral broadening of a weak picosecond pulse in glass produced by an intense picosecond pulse

Abstract
Spectral broadening of a weak 80-μJ picosecond 530-nm laser pulse in a BK-7 glass has been enhanced over the entire spectral band by the presence of an intense millijoule picosecond 1060-nm laser pulse. The spectral distributions of the self-phase modulation and the induced-phase modulation signals are similar. The dominant enhancement mechanism for the induced supercontinuum was determined to be caused by an induced-phase modulation process, not by stimulated four-photon scattering.