Contact Nonlinear Acoustic Diode

Abstract

Nonlinear implementations of acoustic diodes are inherently nonreciprocal and have received continuous attention from the beginning of the research boom for acoustic diodes. However, all the reported nonlinear schemes usually have the shortcomings such as low transmission ratio, action threshold, lack of stability and cumbersome setups. In the present design, we take advantage of extraordinarily large contact acoustic nonlinearity which is several orders of magnitude stronger than material nonlinearity. It is theoretically found that the spectra of the transmitted wave depend on the contact time. It is proven experimentally that the contact nonlinearity can be tamed by adjusting the driving amplitude, the static stress and the elastic constants of the materials. In order to build a compact acoustic diode, a sub-wavelength filter with a sandwich structure is designed. The total length of the acoustic diode is only three eighths of the incident wavelength. The amplitude-dependent behavior of the device exhibits similarities with electronic diodes. A more than 50% transmission ratio is obtained. A robust, stable, compact, highly efficient and solid-state acoustic diode is realized.

Nonreciprocal phonon blockade

“…It cause a shift in the resonance frequency and phase of the propagating phonon mode in the cavity, which has been proved in recent experiments [90]. Such nonreciprocal PB can be used for many acoustic devices, such as acoustic diodes [91][92][93][94][95], which can play a key role in a phonon-basis information network at the few-phonon levels [96].…”

Asymmetric full mode-converting transmission of elastic waves

“…Because of its scientific and technical significance, asymmetric wave propagation has attracted increasing attentions from researchers in various fields, covering acoustics [1], mechanics [2], elastics [3], photonics [4], thermal dynamics [5], and so on. In the acoustic/elastic field, many design strategies have been developed, by exploiting structural asymmetry [6,7], mode conversion [8,9], abnormal reflection and refraction [10][11][12][13][14][15][16][17][18], nonlinearity [19][20][21][22][23][24], time-space modulation [25,26], etc.…”

Acoustic diode realized by asymmetric filter

“…18,19) Some workers introduce extrinsic stimuli to modulate the properties of the host medium in space, time, or both [20][21][22] to break the propagation reciprocity of acoustic waves. Some other scholars exploit intrinsic properties of the media such as structural chirality, 23,24) dissipation, 25) and nonlinearity [26][27][28][29][30] to realize the unidirectional transmission of acoustic waves.…”

“…We have exploited the large contact nonlinear effect to give a design of an acoustic diode. 29) It has ignorable backward transmission, and the forward transmission ratio is great when both the fundamental wave and its harmonics are taken into consideration. Like most designs based on nonlinear effects, compared with the incident fundamental wave, the transmitted wave actually contains rich frequency components, and the waveform of the transmitted wave is also distorted.…”