Experimental research on the longitudinal field generated by a tightly focused beam  

作　　者：张明倩 王佳 田芊 

机构地区：[1]State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University

出　　处：《Chinese Physics B》2013年第4期258-263,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 61177089 and 61227014);the National Basic Research Program of China (Grant No. 2007CB936801)

摘　　要：The longitudinal optical field is a peculiar physical phenomenon that is always involved with the domain of near-field optics. Due to its extraordinary properties, it has recently attracted increasing attention in research and application. In this work, the longitudinal fields generated by the evanescent illumination of tightly focused, different polarized hollow beams are investigated. The focused light fields are numerically simulated according to vector diffraction theory, and their vector analysis is also carried out. The longitudinal fields on the focal plane are demonstrated experimentally using tip-enhanced scanning near-field microscopy. The simulation and experimental results show that the tightly focused radially polarized beam is suited to generating a stronger and purer longitudinal optical field at the focus.The longitudinal optical field is a peculiar physical phenomenon that is always involved with the domain of near-field optics. Due to its extraordinary properties, it has recently attracted increasing attention in research and application. In this work, the longitudinal fields generated by the evanescent illumination of tightly focused, different polarized hollow beams are investigated. The focused light fields are numerically simulated according to vector diffraction theory, and their vector analysis is also carried out. The longitudinal fields on the focal plane are demonstrated experimentally using tip-enhanced scanning near-field microscopy. The simulation and experimental results show that the tightly focused radially polarized beam is suited to generating a stronger and purer longitudinal optical field at the focus.

关 键 词：longitudinal optical field high numerical aperture focusing beam POLARIZATION 

分 类 号：O43[机械工程—光学工程]