Generation of multiple subwavelength focal hole segments using azimuthally polarized hollow Gaussian beam

Abstract

We propose a new approach for generating multiple focal hole segment of sub wavelength size, by tight focusing of phase modulated azimuthally polarized hollow Gaussian beam. The focusing properties are investigated theoretically by vector diffraction theory. We observed that focal segment with multiple focal hole structure separated with different axial distance can be generated by properly tuning the phase of the incident azimuthally polarized hollow Gaussian (HGB) beam. Potential applications of this focal shaping technique are also discussed.