The calculation of the diffraction of the laser beams with a phase singularity on the micro-axicons with using high-performance computing

Abstract

We analyze the diffraction of the laser beam with a vortex phase singularity on the basis of the finite-difference time-domain method (FDTD). It is shown that, when incident beam has phase singularity, increase of the micro-axicon radius leads to extension of the light needle consisting of longitudinal electric field component. The numerical investigations held of the near-field diffraction for the most common and easily implemented types of polarization of the incident beam-linear and circular. © Published under licence by IOP Publishing Ltd.