Broadband acoustic diode by using two structured impedance-matched acoustic metasurfaces

Abstract

An acoustic diode (AD) is proposed and designed based on a mechanism different from the previous designs by using two structured impedance-matched acoustic metasurfaces. This AD can realize unidirectional acoustic transmission within a broad band with high transmission efficiency due to the impedance-matching condition while allowing other entities such as objects or fluids to pass freely. What is more, the backtracking waves that come from the incoming waves can be efficiently prevented and cannot disturb the source. The acoustic pressure field distribution, intensity distribution, and transmission efficiency are calculated by using the finite element method. The simulation results agree well with the theoretical predictions. Our proposed mechanism can experimentally provide a simple approach to design an AD and have potential applications in various fields such as medical ultrasound and noise insulation.

Contact Nonlinear Acoustic Diode

“…Recent years have witnessed a lot of researches addressing on design of a variety of one-way transport acoustic devices. Among them, a rather number of designs are making use of asymmetric scatters 2,3 , mode conversion in wave guides 4,5 , angular-dependent band gap in phononic crystal [6][7][8][9][10][11][12][13] , or abnormal reflection and refraction of metamaterials [14][15][16][17][18] . Strictly speaking, most of these designs don't break the reciprocity when all modes and all ports are considered together.…”

“…Like the active designs, auxiliary devices and consumption of extra energy are needed. 2) The second class of topologies involves taking advantage of intrinsic properties of the media such as structural chirality [25][26][27] , dissipation 17,28 and nonlinearity [29][30][31][32][33][34][35] . For example, C. He et al elegantly realized the inversion of acoustic energy bands at a double Dirac cone, and experimentally demonstrated an acoustic topological insulator and robust one-way sound transport 24 .…”

Towards the conception of complex engineering meta-structures: relaxed-micromorphic modelling of low-frequency mechanical diodes/high-frequency screens

“…In the literature, scientist are mainly focusing on trying to engineer the internal metamaterial's architecture following non-homogeneous patterns (see e.g. [6,7,20,21,22,28,35,41,42,48,49]) or non-elastic constitutive laws [38] so as to create these diodes.…”

Ultra-Broadband Acoustic Diode in Open Bend Tunnel by Negative Reflective Metasurface

“…Wang et al . propose a wideband sound one-way device with impedance-matched sound metasurfaces 23 . However, the design has an obstacle to complexity in experimental realization.…”