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Loss in acoustic metasurfaces: a blessing in disguise

Published online by Cambridge University Press:  14 November 2019

Nikhil JRK Gerard  and
Yun Jing Open the ORCID record for Yun Jing [Opens in a new window]
Nikhil JRK Gerard
Affiliation:
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC27695, USA
Yun Jing*
Affiliation:
Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC27695, USA
*
Address all correspondence to Yun Jing at yjing2@ncsu.edu
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Abstract

From being an unfavorable consequence to finding itself as the intended imaginary part of a non-Hermitian system, loss has truly emerged as more of a friend than a foe in the context of acoustic metasurfaces. With the promising features of sub-wavelength geometries and the rapid advances in manufacturing techniques that can enable their realization, loss becomes a central topic of discussion. Further, the capability of introducing and tailoring loss allows it to serve as a new degree of freedom in passive wavefront shaping devices. In this review, the authors look back at the recent progress in the field of lossy acoustic metasurfaces. The background behind loss in deep sub-wavelength geometries and the instinctive responses to treat them and exploit them are overviewed, followed by more recent works that embrace and tailor their behavior for unconventional applications. The forthcoming years for acoustic metasurfaces thus hold several promising avenues for exploration, with loss as the protagonist.

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Prospective Articles
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MRS Communications , Volume 10 , Issue 1 , March 2020 , pp. 32 - 41
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Copyright © Materials Research Society 2019

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