Non-reciprocal and highly nonlinear active acoustic metamaterials.
Journal Article (Journal Article)
Unidirectional devices that pass acoustic energy in only one direction have numerous applications and, consequently, have recently received significant attention. However, for most practical applications that require unidirectionality at audio and low frequencies, subwavelength implementations capable of the necessary time-reversal symmetry breaking remain elusive. Here we describe a design approach based on metamaterial techniques that provides highly subwavelength and strongly non-reciprocal devices. We demonstrate this approach by designing and experimentally characterizing a non-reciprocal active acoustic metamaterial unit cell composed of a single piezoelectric membrane augmented by a nonlinear electronic circuit, and sandwiched between Helmholtz cavities tuned to different frequencies. The design is thinner than a tenth of a wavelength, yet it has an isolation factor of >10 dB. The design method generates relatively broadband unidirectional devices and is a good candidate for numerous acoustic applications.
Full Text
Duke Authors
Cited Authors
- Popa, B-I; Cummer, SA
Published Date
- January 2014
Published In
Volume / Issue
- 5 /
Start / End Page
- 3398 -
PubMed ID
- 24572771
Electronic International Standard Serial Number (EISSN)
- 2041-1723
International Standard Serial Number (ISSN)
- 2041-1723
Digital Object Identifier (DOI)
- 10.1038/ncomms4398
Language
- eng