Filamentation of femtosecond laser pulses with spatial chirp in air is investigated numerically. Spatiotemporal redistribution of energy occurs initially due to the spatial chirp and is subsequently reinforced by group-velocity dispersion and self-focusing. It induces spatiotemporal rotation of pulse, curved multiple filaments, delay of filament onset distance, and enhancement of supercontinuum generation. The method of introducing spatial chirp to the laser pulse offers a new way to control filaments’ onset, distribution, and supercontinuum enhancement, which would be very useful in their potential applications.
© 2014 Optical Society of America
Original Manuscript: October 22, 2013
Revised Manuscript: December 16, 2013
Manuscript Accepted: December 17, 2013
Published: January 23, 2014
Tingting Xi, Zhijie Zhao, and Zuoqiang Hao, "Filamentation of femtosecond laser pulses with spatial chirp in air," J. Opt. Soc. Am. B 31, 321-324 (2014)