Minaev P. Localization of oscillations in strongly anisotropic and multi-layered systems

The objects of studying are peculiarities of phonon spectra of strongly anisotropic layered crystals, characteristics of localized and quasi-localized states. The aim was to study theoretically the influence of planar defects on dynamical characteristics of strongly anisotropic layered crystals and peculiarities of wave propagation and localization in complex multi-layered crystals. Methods of research are the lattice dynamics methods. It is first shown that characteristics of some types of atomic oscillations in crystals containing planar defects can be described using simple one-dimensional models. The process of resonant wave transmission through an inter-crystal boundary is studied. Based on the data of acoustical and point-contact measurements, the total phonon density of states of VSe2 is reconstructed. The lattice model of VSe2 was proposed and used to calculate the total and partial densities of phonon states. These functions make it possible to see the "local" atomic contributions to crystal dynamics and can be used in further theoretical and experimental research. Sphere of use is the fundamental and applied science.