Wave mixing in coupled phononic crystals via a variable stiffness mechanism

TL;DR

This paper explores wave mixing in coupled phononic crystals with variable stiffness, demonstrating how control signals can manipulate wave transmission, mode selection, and enable functionalities like switching and amplification, akin to an acoustic transistor.

Contribution

It introduces a novel phononic crystal system with variable stiffness that allows wave control, mode selection, and amplification, advancing acoustic device capabilities.

Findings

Control waves can manipulate primary channel transmission.

Wave mode mixing enables modulation effects.

System can perform switching and amplification functions.

Abstract

We investigate wave mixing effects in a phononic crystal that couples the wave dynamics of two channels -- primary and control ones -- via a variable stiffness mechanism. We demonstrate analytically and numerically that the wave transmission in the primary channel can be manipulated by the control channel's signal. We show that the application of control waves allows the selection of a specific mode through the primary channel. We also demonstrate that the mixing of two wave modes is possible whereby a modulation effect is observed. A detailed study of the design parameters is also carried out to optimize the switching capabilities of the proposed system. Finally, we verify that the system can fulfill both switching and amplification functionalities, potentially enabling the realization of an acoustic transistor.