Gluon distribution in proton at soft and hard pp collisions

We analyze the inclusive spectra of hadrons produced in $pp$ collisions at high energies in the mid-rapidity region within the soft QCD and perturbative QCD assuming the possible creation of the soft gluons at low intrinsic transverse momenta $k_t$. From the best description of the LHC data we found the parametrization of the unintegrated gluon distribution which at low $k_t$ is different from the one obtained within the perturbative QCD.Comment: 10 pages, 5 figures. Talk given the 5th joint International HADRON STRUCTURE '11 Conference (HS'11), Tatransk\'a Strba, Slovakia, June 27th - July 1st, 201

High resolution investigation of the domain kinetics in lithium niobate and lithium tantalate single crystals

Static domain patterns produced by application of the external electric field in wide temperature range in single crystals of congruent, stoichiometric and MgO doped lithium niobate LiNbO3 (LN) and lithium tantalate LiTaO3 (LT) were investigated experimentally in great detail. Moreover the domain kinetics has been studied by computer simulation and experimentally in model structure in order to check applicability of the kinetic approach to explanation of the individual domain shape and domain structure evolution for switching from multidomain initial state [1]. The step-by-step kinetic model of the domain growth was realized in the model experiment. Evolution of two-dimensional (2D) domain patterns has been investigated in CLN produced by application of external electric field by 2D electrode grating (Fig. 1). The grating structure has been produced by photolithography and the field has been applied using liquid electrolyte. & more

Nanoscale domain effects in ferroelectrics. Formation and evolution of self-assembled structures in LiNbO₃ and LiTaO₃

We discuss the most interesting nanoscale domain effects resulting in formation and evolution of self-assembled domain structures in various representatives of LiNbO3 family. Several exotic domain kinetic scenarios for complete suppression of the classical wall motion have been revealed. It has been shown that the modification of the surface layer allows to obtain: (1) the wall motion controlled by merging with nanoscale domains generated in front of the moving wall and (2) the discrete switching by enlargement of the web-like self-assembled ensemble of isolated domains. The formation of nanoscale quasi-periodic and self-similar structures during cooling after pulse heating without any application of external electric field was studied. It has been shown that all experimental results can be explained, if the retardation of the bulk screening of the depolarization field is taken into account