Unidirectional acoustic transmission through a prism with near-zero refractive index

We propose a two-dimensional model of acoustic prism comprising metamaterials with near-zero refractive index to yield high efficiency unidirectional transmission and demonstrate an implementation by coiling up space. Due to the acoustic tunneling effect, the waveform is kept consistent between input and output waves, and the transmitted angle can be controlled by reshaping the prism, even in the presence of hard scatterer. A directional waveguide is also designed whose transmission property can be freely switched between all possible states. Our design may have potential for practical applications of acoustic one-way devices in various fields such as ultrasound imaging and treatment.

[1]  Jensen Li,et al.  Extreme acoustic metamaterial by coiling up space. , 2012, Physical review letters.

[2]  Xiang Zhang,et al.  Method for retrieving effective properties of locally resonant acoustic metamaterials , 2007 .

[3]  B. Liang,et al.  An acoustic rectifier. , 2010, Nature materials.

[4]  S. Raghu,et al.  Possible realization of directional optical waveguides in photonic crystals with broken time-reversal symmetry. , 2008, Physical review letters.

[5]  Baowen Li,et al.  Thermal diode: rectification of heat flux. , 2004, Physical review letters.

[6]  Xu Ni,et al.  Tunable unidirectional sound propagation through a sonic-crystal-based acoustic diode. , 2011, Physical review letters.

[7]  N. Fang,et al.  Numerical study of a near-zero-index acoustic metamaterial , 2012 .

[8]  O. A. Kaya,et al.  Refraction-type sonic crystal junction diode , 2012 .

[9]  Xueqin Huang,et al.  Dirac cones at k→=0 in acoustic crystals and zero refractive index acoustic materials , 2012 .

[10]  Yong Li,et al.  Unidirectional acoustic transmission based on source pattern reconstruction , 2012 .

[11]  Bin Liang,et al.  Acoustic diode: rectification of acoustic energy flux in one-dimensional systems. , 2009, Physical review letters.

[12]  Yong Li,et al.  Acoustic focusing by coiling up space , 2012 .

[13]  C Daraio,et al.  Anomalous wave reflection at the interface of two strongly nonlinear granular media. , 2005, Physical review letters.

[14]  J. Tao,et al.  Broadband directional acoustic waveguide with high efficiency , 2012 .