Khizhnyi V. High-frequency electromagnetic excitation of sound in conducting and magnetic structures

The thesis is devoted to solving the problem of electromagnetic excitation of sound in metal, semiconductor heterostructure and magnetic dielectric at frequencies 200-600 MHz. In tungsten at helium temperature under the conditions of spatial and temporal dispersion the row of new effects of deformation mechanism of sound generation is found out. Among them are: excitation of transversal sound modes of different type, anisotropy of deformation potential, nonlinear generation of sound of longitudinal polarization. In semiconductor SiGe/Si heterostructures the effect of sound generation by the HF - electric field is discovered and his features are studied. The model of sound generation related to the coulomb mechanism of interaction of spatially non-uniform distribution of HF- field and charges in heterostructure is offered. In antiferromagnet iron borate the effect of birefringence and his thin structure are first found out and studied. The model of effect connected to the induced uniaxial base anisotropy is proposed.The contribution of piezomagnetism to the magnetoelastic energy of crystal, explaining row of first found out effects such as: softening of nonmagnetic elastic mode, HF-magnetic generation of longitudinal sound, magnetic field dependence of longitudinal sound resonances and their features, is determined.