title: Achievement of longitudinally polarized focusing with long focal depth by amplitude modulation.
abstract: The longitudinal component of a focused beam is split into two parts along the optical axis to obtain a longitudinally polarized long focal depth using amplitude filtering based on Euler transformation and a radially polarized Bessel-Gaussian beam. Numerical results indicate that long focal depth and FWHM can be easily achieved with 9λ and 0.8λ, respectively. A radially polarized beam can be converted into a longitudinally polarized beam with a conversion efficiency of 51.0%. It can therefore be believed that the proposed scheme can be widely used to generate a longitudinally polarized beam for particle acceleration, laser cutting, and optical trapping.
authors.affiliation: Center of Ultra-precision Optoelectronic Instrument, Harbin Institute of Technology, Harbin 150001, China. linjie@hit.edu.cn
authors.forename: Jie
authors.initials: J
authors.lastname: Lin
authors.forename: Ke
authors.initials: K
authors.lastname: Yin
authors.forename: Yuda
authors.initials: Y
authors.lastname: Li
authors.forename: Jiubin
authors.initials: J
authors.lastname: Tan