We demonstrate that the group velocities of interacting pulses can be
adjusted by pulse tilting to optimize second-harmonic pulse compressio
n for a variety of nonlinear crystals and wavelengths. As an experimen
tal proof we present results of ninefold compression of 1.3-ps Nd:glas
s laser pulses in beta-barium berate crystal. (C) 1997 Optical Society
of America.