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Updated: Aug 4, 2025

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Ultra-sparse near-perfect sound absorbers
Jun Ji1, Junfei Li2, Steven A Cummer2
1Graduate Program in Acoustics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Abstract:
There is a trade-off between the sparseness of an absorber array and its sound absorption imposed by wave physics. Here, near-perfect absorption (99% absorption) is demonstrated when the spatial period of monopole-dipole resonators is close to one working wavelength (95% of the wavelength). The condition for perfect absorption is to render degenerate monopole-dipole resonators critically coupled. Frequency domain simulations, eigenfrequency simulations, and the coupled mode theory are utilized to demonstrate the acoustic performances and the underlying physics. The sparse-resonator-based sound absorber could greatly benefit noise control with air flow and this study could also have implications for electromagnetic wave absorbers.
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