Designing Switchable Phononic Crystal-Based Acoustic Demultiplexer

Abstract

We present the design procedure for switchable acoustic demultiplexers based on a fluid-fluid phononic crystal (PnC) platform. It consists of a T-shaped PnC waveguide coupled to two output waveguide ports through two dissimilar point-defect cavities. The PnC platform consists of a periodic array of infinitely long rods of water (inclusions) embedded in mercury background. The waveguides are made by the removal of a row or a column of inclusions from the PnC, while the fluid in one of the two dissimilar cavities is methyl nonafluorobutyl ether (MNE) and in the other is ethyl nonafluorobutyl ether (ENE). The difference in the sound velocity in MNE and ENE provides an adequate difference in the dissimilar cavities resonant modes, required for the demultiplexing functionality of the designed structure. The different dependences of the sound velocities in these two fluids on temperature have also enabled the switching of the multiplexed channel, simply by appropriately changing the cavities temperature.

Experimental full wavefield reconstruction and band diagram analysis in a single-phase phononic plate with internal resonators

“…Due to this property, phononic plates received great attention because of their potential for technological applications: structural health monitoring [28,29], wave switching [30] and demultiplexing [31], micro-electro-mechanical systems [32,32], cloaking [33], to cite a few. Among the possible configurations, phononic plates made of single or multiple constituents have been considered, including periodic distributions of inclusions, pillars / gratings on the plate surfaces, and empty holes [34].…”

Reconfigurable locally resonant surface acoustic demultiplexing behavior in ZnO-based phononic crystal

“…Reflection and isolation of elastic/acoustic waves in phononic crystals (PNCs), which consist of a periodic array of scatterers, have led to many applications for PNCs in waveguides, resonators, energy harvesters, telecommunication filters, couplers, demultiplexers, and also sensors. [1][2][3][4][5][6][7][8][9][10][11][12] On the other hand, surface acoustic wave (SAW) devices have shown promising applications, ranging from various sensing fields to the signal processing and wireless telecommunication fields, such as RF filters and duplexers. [13][14][15][16][17][18] PNCs, in certain conditions, can create bandgaps for SAWs as well.…”

Fragile topologically protected perfect reflection for acoustic waves

“…Acoustic crystals are a class of artificially engineered metamaterials with fascinating properties, which provide a powerful and flexible scheme to confine, guide, and reflect acoustic waves, thereby forming cavities, waveguides, and mirrors [22][23][24][25][26][27][28][29]. Coupled architectures of acoustic cavities and waveguides are favorable for many prominent acoustic devices, such as switches, filters, and logic elements [30][31][32][33][34]. However, the quality of these acoustic devices is very sensitive to the fabrication defects, that is, the state-of-the-art acoustic devices show strong dependence on manufacturing capability.…”