Generation of coherent XUV vector/vortex beams in Argon gas jets
Abstract
We report an experimental demonstration of vector/vortex high-order harmonic beams produced in Argon gas jets. An orthogonal two-color pump was used to generate polarization-structured vector and vortex beams. In the experiment, short 60 fs laser pulses propagated through phase-modifying optical elements (S-waveplate) or a vortex spiral phase plate (SPP), a thin 0.2 mm second harmonic crystal, and an Argon gas jet. The propagation of a radially polarized vector beam in the orthogonal polarization two-color pump scheme results in the generation of spatially structured odd- and even-order harmonics with variably polarized components along the beam profile. Intermediate states between radially and azimuthally polarized vector beams produce harmonics with twisted wavefronts.