Generation of extended filaments of femtosecond pulses in air by use of a single-step phase plate.
We experimentally demonstrate that by use of a phase plate that is placed between an adjustable aperture and a focusing lens, the length of the filament can be dramatically extended in air with a femtosecond laser pulse. In addition, the far-field beam profile captured after the filament indicates that the supercontinuum is strongly confined on axis, and a single filament appears to be attainable at relatively high input pulse power when the phase plate is used.
Fu
Yuxi
Y
State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800, China.
Xiong
Hui
H
Xu
Han
H
Yao
Jinping
J
Zeng
Bin
B
Chu
Wei
W
Cheng
Ya
Y
Xu
Zhizhan
Z
Liu
Weiwei
W
Chin
See Leang
SL