Manifestation of spatial chirp in femtosecond noncollinear optical parametric chirped-pulse amplifier

In this paper the results of the theoretical and experimental study of spatiotemporal distortions emerging in noncollinear optical parametric chirped-pulse amplifiers are presented. In a noncollinear parametric amplifier, when the pulse fronts of the pump and signal are not matched, the signal pulse becomes tilted and, aside from angular dispersion, has a spatial chirp. The expressions relating the magnitudes of the acquired spatial chirp and angular dispersion to the temporal chirp of the signal pulse are derived. It is shown that the magnitudes of the induced spatial chirp and angular dispersion decrease at different rates with the increase of the signal pulse temporal chirp and, for the large temporal chirp, the spatial chirp mainly contributes to the pulse-front tilt of the signal, whereas the induced signal pulse tilt is independent of the signal pulse temporal chirp, but is always smaller than the tilt of the pump pulse. ©2011 Optical Society of America