Finite Element Analysis of a Phononic Crystal at Gigahertz Frequencies
In this paper, the vibrational behavior of a phononic crystal is studied at gigahertz frequencies. The phononic crystal is comprised of a silicon slab with tungsten inclusions filtering out waves within the frequency range of 0.7 GHz to 1.1 GHz. Two-dimensional harmonic finite element analysis (FEA) is employed to model the transmission of stresswaves launched from a transmitter and passing through the crystal. The numerical results are compared with another prevalent numerical method, finite difference time domain (FDTD), as well as with experimental results. Comparisons made between the numerical approaches and experimental approach, show that the harmonic finite element analysis agrees well with experiment and potentially can explain the experimental results more precisely than FDTD. This more favorable comparison is attributed to a resonance that occurs between the transmitter and the phononic crystal.