Asymmetric acoustic transmission through near-zero-index and gradient-index metasurfaces
Abstract
We present a design of acoustic metasurfaces yielding asymmetric transmission within a certain frequency band. The design consists of a layer of gradient-index metasurface and a layer of low refractive index metasurface. Incident waves are controlled in a wave vector dependent manner to create strong asymmetric transmission. Numerical simulations show that the approach provides high transmission contrast between the two incident directions within the designed frequency band. This is further verified by experiments. Compared to previous designs, the proposed approach yields a compact and planar device. Our design may find applications in various scenarios such as noise control and therapeutic ultrasound.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 30, 2016
- Source ID
- 10.1063/1.4953264
Entities
People
- Chen Shen
- Junfei Li
- Steven A. Cummer
- Yangbo Xie
- Yun Jing
Organizations
- Duke University
- North Carolina State University
- Office of Naval Research