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Updated: Jun 5, 2025

Characterizing Dissipative Elastic Metamaterials Produced by Additive Manufacturing
Published on: June 28, 2024
An acoustic metamaterial with space-time modulated densitya)
1Huzhou Key Laboratory of Green Energy Materials and Battery Cascade Utilization, School of Intelligent Manufacturing, Huzhou College, Huzhou, Zhejiang 313000, China.
Abstract:
Space-time modulation opens the door for unprecedented wave behavior control, such as nonreciprocal wave manipulation. Here is proposed a one-dimensional space-time modulated membrane system aiming to realize a kind of acoustic metamaterial with space-time modulated effective density. Three different approaches, namely, the effective medium method, transfer matrix method, and time-domain simulation, are applied to analyze the acoustic response of the system under a monochromatic incidence. Results show that the proposed metamaterial can support two different nonreciprocal acoustic functionalities, namely, unidirectional parametric amplification and parametric frequency conversion, when different modulation profiles are enforced.
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