Tight Focusing of Radially and Azimuthally Polarized Vortex Beams through a Dielectric Interface

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2008,（5）
• 页码范围: 1664-1667
• 页数: 4页
• 语种: 英文

摘要

Based on vectorial Debye theory,tight focusing of radially and azimuthally polarized vortex beams passing through a dielectric interface are studied.The intensity distribution in the focal region is illustrated by numerical calculations.We show the influence of numerical-aperture (NA) on the full-width at half maximum (FWHM) of the focal spot or the focal hole.It has been found that compared with the azimuthally polarized Bessel-Gaussian (BG) beams,the longitudinal component in the z direction of the radially polarized BG beams has no influence on the FWHM of the focal spot and hole,but enhances the total light intensity.