中国物理B ›› 2018, Vol. 27 ›› Issue (12): 124302-124302.doi: 10.1088/1674-1056/27/12/124302

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Bidirectional asymmetric acoustic focusing with two flat acoustic metasurfaces

Di-Chao Chen(陈帝超), Xing-Feng Zhu(朱兴凤), Qi Wei(魏琦), Da-Jian Wu(吴大建)   

  1. Jiangsu Key Laboratory on Opto-Electronic Technology, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
  • 收稿日期:2018-08-15 修回日期:2018-09-11 出版日期:2018-12-05 发布日期:2018-12-05
  • 通讯作者: Xing-Feng Zhu, Da-Jian Wu E-mail:zhuxingfeng@njnu.edu.cn;wudajian@njnu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11704193, 11674175, and 11704192), the “333” Project of Jiangsu Province, China (Grant No. BRA2017451), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province, China (Grant No. KYCX18_1185).

Bidirectional asymmetric acoustic focusing with two flat acoustic metasurfaces

Di-Chao Chen(陈帝超), Xing-Feng Zhu(朱兴凤), Qi Wei(魏琦), Da-Jian Wu(吴大建)   

  1. Jiangsu Key Laboratory on Opto-Electronic Technology, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China
  • Received:2018-08-15 Revised:2018-09-11 Online:2018-12-05 Published:2018-12-05
  • Contact: Xing-Feng Zhu, Da-Jian Wu E-mail:zhuxingfeng@njnu.edu.cn;wudajian@njnu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11704193, 11674175, and 11704192), the “333” Project of Jiangsu Province, China (Grant No. BRA2017451), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province, China (Grant No. KYCX18_1185).

摘要:

We design an asymmetric transmission system (ATS) with two flat acoustic metasurfaces (AMs) to yield bidirectional asymmetric acoustic focusing (BAAF). The acoustic waves could be focused on both sides of the ATS with different focal lengths and intensities. To achieve high intensity energy concentration, the accelerating acoustic beams are selected to realize the BAAF. The working bandwidth of the BAAF based on our ATS could reach~0.4 kHz. It is found that by adjusting the distance between two flat AMs, the focal length and intensity of the bidirectional focusing could easily be modulated. Because the distance between two flat AMs is large enough, the BAAF even could be converted into a unidirectional acoustic focusing. The proposed BAAF may find applications in non-destructive evaluation, biomedical imaging and medical diagnosis.

关键词: asymmetric focusing, acoustic metasurface, phase manipulation

Abstract:

We design an asymmetric transmission system (ATS) with two flat acoustic metasurfaces (AMs) to yield bidirectional asymmetric acoustic focusing (BAAF). The acoustic waves could be focused on both sides of the ATS with different focal lengths and intensities. To achieve high intensity energy concentration, the accelerating acoustic beams are selected to realize the BAAF. The working bandwidth of the BAAF based on our ATS could reach~0.4 kHz. It is found that by adjusting the distance between two flat AMs, the focal length and intensity of the bidirectional focusing could easily be modulated. Because the distance between two flat AMs is large enough, the BAAF even could be converted into a unidirectional acoustic focusing. The proposed BAAF may find applications in non-destructive evaluation, biomedical imaging and medical diagnosis.

Key words: asymmetric focusing, acoustic metasurface, phase manipulation

中图分类号:  (Ultrasonics, quantum acoustics, and physical effects of sound)

  • 43.35.+d
43.25.+y (Nonlinear acoustics) 43.38.+n (Transduction; acoustical devices for the generation and reproduction of sound)