Building on our theoretical work in transformation acoustics, we are actively involved in the field of acoustic metamaterials, in which we engineer artificial materials to exhibit unusual and useful acoustic material properties. Properties not found in natural materials, such as strong effective mass anisotropy, are needed for transformation acoustics designs, but others such as negative effective modulus or mass are also useful for applications.
Our accomplishments in acoustic metamaterials include the design and experimental demonstration of a metamaterial with strongly anisotropic effective mass, and a gradient refractive index acoustic lens in air. We also designed and demonstrated one of the first acoustic cloaking shell in air using the concept of transformation acoustics.Some of Our Recent Papers on Acoustic Metamaterials
Using optimization to design an improved acoustic lens: Li, D., L. Zigoneanu, B.-I. Popa, and S. A. Cummer (2012), Design of an acoustic metamaterial lens using genetic algorithms
, Journal of the Acoustical Society of America, v. 132, 2823-2833. [pdf reprint
Design and demonstration of an acoustic metamaterial lens: Zigoneanu, L., B.-I. Popa, and S. A. Cummer (2011), Design and measurements of a broadband 2D acoustic lens
, Phys. Rev. B., v84, 024305. [pdf reprint
Pretty much what the title says: Zigoneanu, L., B.-I. Popa, A. Starr, and S. A. Cummer (2011), Design and measurements of a broadband 2D acoustic metamaterial with anisotropic effective mass density
, J. Appl. Phys., v. 109, 054906. [pdf reprint