Polarization States in 2D Phononic Crystals and Phononic Crystal Waveguides
We investigate, using the Plane Wave Expansion method and an energy balance criterion, the polarization states of elastic waves in a two dimensional phononic crystal made of vacuum holes in a silicon host matrix. Pure modes can be identified for the out of plane polarization while a continuous variation of the in-plane polarization with the Bloch wave vector can be observed. The study is then extended to two-dimensional phononic crystal waveguides by using the super- cell technique. The dependence of the elastic wave polarization state on the wave guide width is investigated and shows as well a continuous variation with the Bloch wave vector. Moreover, the variation of the width of the waveguide can be used to tune both the dispersion and the polarization of guided waves.
KeywordsElastic Wave Phononic Crystal Bulk Acoustic Wave Waveguide Width Plane Wave Expansion Method
Unable to display preview. Download preview PDF.