Acoustic 1 × 2 demultiplexer based on fluid-fluid phononic crystal ring resonators

Abstract

Abstract We report the design procedure for an acoustic demultiplexer based on a fluid-fluid phononic crystal (PnC) platform. It consists of a line defect waveguide coupled to two output waveguides through two dissimilar ring resonator cavities (RRC). The multimode nature of RRC makes some advantages like adaptability in structure design, scalability in size and flexibility in mode design. The periodic array of infinitely long rods of water (Inclusions) is embedded in the mercury matrix to form the PnC platform. We investigate the effects of the different radii of the inner rods of the RRC on the transmission spectra and quality factor of the proposed structure. The dispersion diagram and transmission coefficient have been calculated using Plane Wave Expansion (PWE) and Finite Difference Time Domain (FDTD) methods. Numerical results show that the interchannel crosstalks are less than −32 dB and the quality factor (Q) of the structure with the center frequencies of 63.960 KHz and 73.312 KHz are Q1 = 3997 and Q2 = 8145 respectively. Moreover, we show the effects of the different temperatures and pressures on the device performance that the potential of sensing temperature and pressure makes the proposed structure also has usability as an acoustic sensor.