The Influence of the Phase Shift of the Effective Density Vibrations of Layers on the Wave Propagation in Quasi-One-Dimensional Binary Phononic Crystals

Modern smart materials allow for controlling their properties through external factors such as magnetic, electric, or pressure fields. Using these materials, it is possible to make dynamic phononic crystals with time-varying material parameters. A sinusoidal signal propagating in a static material at the boundary of the media with a dynamic material changes its character to a wave spectrum. Each boundary of the media broadens the spectrum of the propagating wave. These phenomena significantly affect the propagation of a mechanical wave in dynamic phononic crystals by changing the distribution of band gaps. By influencing the frequency and phase shifts of changes in material properties, it is possible to control the operation of phononic crystals, which may allow for the design of new types of smart phononic devices.