Study on band gap properties of two-dimensional 8-fold quasi-periodic phononic crystals

For the two-dimensional (2D) 8-fold solid-fluid quasi-periodic photonic nanocrystal (QPNC) (steel-water system), the transmission spectra of the systems with different sizes are obtained by experimentation. At the same time, combined with the supercell method, the finite element method (FEM) is used to calculate the dispersion curves and transmission spectrum of the system. The transmission spectra obtained by means of these two methods are in good agreement with each other, but the band gaps appearing in the transmission spectrum calculated using the FEM are clearer than those obtained via experimentation. The dispersion curves of the 2D 8-fold solid-fluid QPNC can be well studied by using the supercell which only contains its center puzzle.