Jacek Piłka
supervisor: Mirosław Karpierz
Nematic liquid crystals are in the researchers’ spotlight for many years due to their unique properties including nonlocal response associated with the large reorientational nonlinearity making them a very useful optical material. Among others they allow for easy manipulation of light beams, both phase and polarization as well as modification of angular momentum. Recently, it has been shown both experimentally and theoretically that employing nematic liquid crystals as nonlinear, nonlocal media with reorientational nonlinearity leads to stabilization of nonlinear vortex beam.
This work mainly focuses on the novel polarization converter. Such setup containing three different nematic liquid crystal cells can convert linearly polarized gaussian beam into one of eight polarization states including space-variant ones. The device is electrically steered allowing for an easy integration with an automated setup and works in a wide spectrum. Addition of glass spherical phase plate initiating a phase rotation then can results with a single setup for linear polarized gaussian – vector vortex beam conversion.
The second presented topic will be the interaction of a linearly polarized high-power vortex and a low-power gaussian beams co-propagating in nematic liquid crystal. Due to the reorientation of molecules in medium, the first one will generate a waveguide for the second, however it will also result with appearing of a new, low-power vortex with the same charge as high-power beam.