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It is well known that the alignment of liquid crystals can be realized by rubbing or photoalignment technologies. Recently nonlinear laser lithography was introduced as a fast, relatively low-cost method for large area nano-grating fabrication based on laser-induced periodic surface structuring. In this letter for the first time the usage of the nonlinear laser lithography as a perspective method of the alignment of nematics was presented. By nonlinear laser lithography, microgrooves with about 1 {\mu}m period were formed on Ti layer. The microstructured Ti layer was coated with oxidianiline-polyimide film with annealing of the polymer followed without any further processing. Aligning properties of microstructured Ti layers were examined with combined twist LC cell. The dependencies of the twist angle of LC cells and azimuthal anchoring energy of layers on scanning speed and power of laser beam during processing of the Ti layer were the focus of our studies as well. The maximum azimuthal anchoring energy, obtained for pure microstructured Ti layer, is comparable with photoalignment technology. It was found that the deposition of polyimide film on microstructured Ti layer leads to the gain effect of the azimuthal anchoring energy. Also, AFM study of aligning surfaces was carried out., Comment: 16 pages, 4 figures

The peculiarities of the femtosecond filamentation in Kerr media has been studied using a set of time-resoling experimental techniques. These include the temporal self-compression of a laser pulse in the filamentation mode, repulsive and attractive interactions of filaments, and influence of the birefringence on the filamentation. The propagation of femtosecond laser pulses at the 1550-nm wavelength in c-Si is studied for the first time using methods of time-resolved transmission microscopy. The nonlinear widening of the pulse spectrum due to the Kerr- and plasma-caused self-phase modulation is recorded.

Spatio-temporal transformation of the femtosecond laser pulses at 1550 nm wavelength in c-Si is observed using the methods of time-resolved microscopy. The temporal dynamics of the pulse manifests itself both in widening of the frequency spectrum and in the change of on-axis time-width. It is shown, that along with Kerr effect, two-photon absorption also contributes to the temporal reshaping of the laser pulse. Despite the fact that absorption length for green light in c-Si is as small as 1 µm, generation of visible third harmonics was also observed in c-Si. Acknowledgements We acknowledge support from the NAS of Ukraine and the Scientific and Technological Research Council of Turkey (TUBITAK) (a joint research project 114F256), Ukrainian State Fund for Fundamental Research (Project F73/23805), as well as from the Science and Technology Center in Ukraine (Project 6174).

Femtosecond laser-based Nonlinear Laser Lithography (NLL) was applied to AISI 316L stainless steel, which requires surface modification to achieve satisfactory tribological behaviour. NLL advances over the well-known Laser Induced Periodic Surface Structures (LIPSS) in terms of uniformity and long-range order of high speeds, over large areas. A galvanometric scanner head was used for an high production rate. Dry and lubricated sliding tests, considering different orientations of the nanotexture showed that COF values after NLL treatment are significantly lower. In lubricated tests, COF values of NLL-treated surfaces are nearly half the values of untreated surfaces, whereas the difference further increases when measured in dry conditions, where the orientation of the surface texturing influences the results.