Gorb A. Mass and charge transport phenomena stimulated by ultrasound waves in lithium niobate plates

The thesis is devoted to experimental and theoretical investigations of phenomena of mass and charge transport stimulated by ultrasound waves in lithium niobate plates of different cuts. In this work the main characteristics of acoustic waves in the metallized plates of piezoelectric LiNbO3 of YZ-, XZ- and ZY-cuts have been theoretically studied. The regularities obtained have been applied to the studies of the transport of micro grains of powder disposed on the surface of lithium niobate plates of different cuts. It was revealed that the spatial distribution of photoluminescence intensity in a GaAs/AlGaAs semiconductor heterostructure changes under the influence of piezoelectric fields, created by the plate-acoustic duct LiNbO3. The model of carrier transport in the plane of quantum well, which explains the features of the mentioned redistribution has been proposed. The method of sonochemical reaction has been applied to obtain nano-crystalline powders of zink sulphide, doped by manganese ions, whichby their physical parameters are similar to nanopowders, obtained by the standart chemical method.