Acoustic one-way mode conversion and transmission by sonic crystal waveguides

Abstract

Abstract:We proposed a scheme to achieve one-way acoustic propagation and even-odd mode switching in two mutually perpendicular sonic crystal waveguides connected by a resonant cavity.The even mode in the entrance waveguide is able to switch to odd mode in the exit waveguide through a symmetry match between the cavity resonant modes and the waveguide modes. Conversely, the odd mode in the exit waveguide is unable to be converted into the even mode in the entrance waveguide as incident waves and eigenmodes are mismatched in their symmetries at the waveguide exit. This one-way mechanism can be applied to design an acoustic diode for acoustic integration devices and can be used as a convertor of the acoustic waveguide modes.1 Shiliang Ouyang and Hailong He contributed equally to this work. a)

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.…”

Acoustic topological one-way waveguides with tunable widths using spinning components

“…Phononic crystals [1][2][3] and acoustic metamaterials [4][5][6] provide versatile platforms for manipulating the acoustic waves in novel ways, such as super-lensing [7], cloaking [8], unidirectional radiation [9][10][11] and oneway waveguiding [12,13]. Recently, there has been a surge of interest in topological physics.…”

Ultra-broadband asymmetric acoustic transmission with single transmitted beam

“…[14][15][16][17][18] Due to the intrinsic limitations of nonlinear effects, including the inherent signal distortions and transmission efficiency, etc., more attentions have been focused on the asymmetric acoustic transmission (AAT). Several linear acoustic devices have been proposed to realize the AAT, such as acoustic gratings, [19][20][21][22][23][24][25] phononic crystals, [26][27][28][29][30] metamaterials, [31,32] and metasurfaces, [33][34][35] which have advantages of the high transmission efficiency and broad bandwidth of the AAT. However, for most of these AAT structures, the positive transmitted waves are usually two beam, [22] three beam, [19,20] multiple beam, [23,24,26] or distorted waveform in waveguides, [28][29][30]34,35] and it is difficult to concentrate the transmitted energy into a signal acoustic beam.…”

“…Several linear acoustic devices have been proposed to realize the AAT, such as acoustic gratings, [19][20][21][22][23][24][25] phononic crystals, [26][27][28][29][30] metamaterials, [31,32] and metasurfaces, [33][34][35] which have advantages of the high transmission efficiency and broad bandwidth of the AAT. However, for most of these AAT structures, the positive transmitted waves are usually two beam, [22] three beam, [19,20] multiple beam, [23,24,26] or distorted waveform in waveguides, [28][29][30]34,35] and it is difficult to concentrate the transmitted energy into a signal acoustic beam. In this context, the AAT effect with a single transmitted beam has been obtained based on the asymmetric phase modulation.…”