Strengthening the longitudinal component of the sharply focused electric field by means of higher-order laser beams.

We study the sharp focusing of differently polarized low-order and high-order beams, including Bessel and Laguerre-Gaussian (LG) modes, to compare them using several criteria: the size of a light spot, the intensity ratio of the central peak and sidelobes, and the intensity of the longitudinal electric field component. The experiments performed using the near-field microscopy techniques are in general agreement with the results of the numerical simulation. We have validated the growth of the longitudinal component in the focus for high-order modes at moderate NA=0.6-0.8, and essential lower sidelobes of Bessel modes, in comparison with LG modes.

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