Acoustic focusing by symmetrical self-bending beams with phase modulations

We propose a scheme for generating high-efficient acoustic focusing capable of circumventing obstacles in the propagating medium. This distinct feature that is highly desirable for practical applications is realized by employing two symmetrical Airy beams, and a different type of acoustic lens is designed by using a zero-index medium to provide the required phase profile with extremely high resolution. Furthermore, the scheme has the flexibility of generating tunable focal length. We anticipate our design to open possibilities for the design of acoustic lens and have potential applications in various important scenarios such as biomedical imaging/therapy and non-destructive evaluation.

[1]  Yong Li,et al.  Metascreen-Based Acoustic Passive Phased Array , 2015 .

[2]  Hong-xiang Sun,et al.  Acoustic focusing by metal circular ring structure , 2015 .

[3]  Richard W Ziolkowski,et al.  Propagation in and scattering from a matched metamaterial having a zero index of refraction. , 2004, Physical review. E, Statistical, nonlinear, and soft matter physics.

[4]  Daniel Torrent,et al.  Sound focusing by gradient index sonic lenses , 2010, 1006.2701.

[5]  S. M. Wang,et al.  Plasmonic Airy beam generated by in-plane diffraction. , 2011, Physical review letters.

[6]  T. P. Martin,et al.  Elastic shells with high-contrast material properties as acoustic metamaterial components , 2012 .

[7]  Gengkai Hu,et al.  Superlensing effect of an anisotropic metamaterial slab with near-zero dynamic mass , 2011, 1105.0001.

[8]  Bin Liang,et al.  Ultra-broadband absorption by acoustic metamaterials , 2014 .

[9]  Zhi Ning Chen,et al.  Manipulation of acoustic focusing with an active and configurable planar metasurface transducer , 2014, Scientific Reports.

[10]  C. Yun,et al.  Piezoelectric sensor based nondestructive active monitoring of strength gain in concrete , 2008 .

[11]  Demetrios N. Christodoulides,et al.  Observation of accelerating Airy beams. , 2007 .

[12]  F. Gleeson,et al.  High-intensity focused ultrasound for the treatment of liver tumours. , 2004, Ultrasonics.

[13]  D. Torrent,et al.  Acoustic metamaterials for new two-dimensional sonic devices , 2007 .

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

[15]  Xiasheng Guo,et al.  Acoustic non-diffracting Airy beam , 2015 .

[16]  Yong Li,et al.  Experimental realization of full control of reflected waves with subwavelength acoustic metasurfaces , 2014, 1407.1138.

[17]  N. Fang,et al.  Ultrasonic metamaterials with negative modulus , 2006, Nature materials.

[18]  Bin Liang,et al.  Dispersionless Manipulation of Reflected Acoustic Wavefront by Subwavelength Corrugated Surface , 2015, Scientific Reports.

[19]  Thomas Pertsch,et al.  Generation and near-field imaging of Airy surface plasmons. , 2011, Physical review letters.

[20]  Dong Zhang,et al.  Comparative Study of Lesions Created by High-Intensity Focused Ultrasound Using Sequential Discrete and Continuous Scanning Strategies , 2013, IEEE Transactions on Biomedical Engineering.

[21]  Yong Li,et al.  Unidirectional acoustic transmission through a prism with near-zero refractive index , 2013 .

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

[23]  Bin Liang,et al.  Three-dimensional Ultrathin Planar Lenses by Acoustic Metamaterials , 2014, Scientific Reports.

[24]  Xu Ni,et al.  Acoustic cloaking by a near-zero-index phononic crystal , 2014 .

[25]  Jing Chen,et al.  Rapid MR‐ARFI method for focal spot localization during focused ultrasound therapy , 2011, Magnetic resonance in medicine.