PROCEEDINGS ARTICLE | May 16, 2017
Proc. SPIE. 10228, Nonlinear Optics and Applications X
KEYWORDS: Ultrafast phenomena, Diffraction, Monochromatic aberrations, Mirrors, Visible radiation, Metrology, Femtosecond phenomena, Polarization, Photography, Wavefronts, Kerr effect, Distortion, Telecommunications, Nonlinear optics, Spherical lenses, Laser optics, Pulsed laser operation
The results of formation conditions studies of a highly directional supercontinuum (SC) in a visible spectrum range obtained upon aberration spherical-mirror focusing of a radiation pulse with a wavelength of 940 nm, duration of 70 fs, and energy of 8–15 mJ are presented. It is shown that after visible filament there are two directed white light beams diverging relative to each other at an angle of 1.4<sup>0</sup> . Formation every light beam occurs through a gradual conversion of the spectral composition from long wavelength to short wavelength (to 350 nm) in a spatially stable structure similar to a soliton with a transverse dimension ≤ 300 μm. The nature of the appearance these beams is due to formation of two zones with higher intensity before meridional plate owing to the distortion of the wavefront of the laser beam in conditions of the astigmatism and the Kerr effect. In result two minima in the phase distribution located outside the beam axis are realized, which lead to the appearance of two off-axis areas with higher radiation intensity and as a consequence of this the formation of two highly directional laser beams.
