title: Femtosecond laser filament array generated with step phase plate in air.
abstract: Femtosecond laser filament arrays are generated in air by using three kinds of step phase plates with π phase lag, namely, the semicircular phase plate (SCPP), the quarter-circle phase plate (QCPP) and eight-octant phase plate (EOPP). Experimental results and simulations show that filament arrays consisting of two, four and eight filaments, respectively, are produced by three phase plates. The transverse patterns of the filament arrays are determined by the geometrical shapes of the phase plates. At the same time, the separation distances are found to vary with the focal lengths of the used lenses. We further propose that by using an axicon, filament array in the form of ring shape could be realized while the lengths of the filaments could be significantly elongated at the same time. Our study has suggested a realistic method to generate filament array by the step phase plate with π phase lag.
authors.affiliation: Institute of Modern Optics, Nankai University, Key Laboratory of Optical Information Science and Technology, Ministry of Education, Tianjin 300071, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Gao
authors.forename: Wei
authors.initials: W
authors.lastname: Chu
authors.forename: Guoliang
authors.initials: G
authors.lastname: Yu
authors.forename: Bin
authors.initials: B
authors.lastname: Zeng
authors.forename: Jiayu
authors.initials: J
authors.lastname: Zhao
authors.forename: Zhi
authors.initials: Z
authors.lastname: Wang
authors.forename: Weiwei
authors.initials: W
authors.lastname: Liu
authors.forename: Ya
authors.initials: Y
authors.lastname: Cheng
authors.forename: Zhizhan
authors.initials: Z
authors.lastname: Xu
mesh_terms: D000388:Air; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007834:Lasers