Representation and focusing properties of higher-order radially polarized Laguerre–Gaussian beams

Abstract

A method based on higher-order Poincaré sphere was proposed to represent the states of polarization of higher-order radially polarized Laguerre–Gaussian (LG) vectorial beams (VBs). And the focusing properties of such LG beams of different radial orders focused by a high-NA lens were discussed. By tuning the ratio of the pupil radius to the waist of the incident beams, some cage-like or needlelike electric intensity field is generated in the focal region for several specific LG VBs with high order. Modulated by diffractive optical elements, the shape of the focal field shows novel behaviors such as splitting of cage-like modes, which provides potentially a more flexible control over micro-particles.

Keywords:

• vectorial beams
• radially polarized Laguerre–Gaussian beams
• higher-order Poincaré-sphere

Additional information

Funding

This work was supported in part by the National High Technology R&D Program of China (863 Program) [grant number 2012AA040406]; the National Natural Science Foundation of China [grant number 11374063].