Realization of broadband asymmetric transfer of acoustic energy in a composite waveguide system with dynamically detuned supermodes

The emergence of acoustic metamaterials has facilitated the anomalous manipulation of acoustic waves over the past decades. Recently, attention has shifted toward asymmetric acoustic energy transfer. In this study, we design a composite waveguide structure that consists of three waveguide units, which support three odd-symmetric supermodes with dynamically detuned propagation constants. Utilizing the rapid adiabatic passage technique, we numerically and experimentally demonstrate three distinct adiabatic transfers of acoustic energies in the designed composite waveguide structures. For the absence of crossing points in the detuned supermode propagation constants, a complete recovery of the acoustic energy is achieved in the excited waveguide unit. When three detuned supermode propagation constants are configured with either one or two crossing points throughout the entire adiabatic process, the composite waveguide structure can be used to selectively realize the symmetric transfer or asymmetric cyclic transfer of the acoustic energy among the three waveguide units. Furthermore, the asymmetric cyclic transfer of the acoustic energy renders the broadband and robust characteristics. Our findings offer promising applications in the design of acoustic circulators and underwater communication systems.