Bidirectional asymmetric acoustic focusing with two flat acoustic metasurfaces<xref rid="cpb_27_12_124302fn1" ref-type="fn">*</xref><fn id="cpb_27_12_124302fn1"><label>*</label><p>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

Bidirectional asymmetric acoustic focusing with two flat acoustic metasurfaces**

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).

Chen Di-Chao, Zhu Xing-Feng^†, Wei Qi, Wu Da-Jian^‡

(color online) Acoustic field distributions of acoustic plane waves impinging normally on ATS with L = 12.5λ₀ for (a) PD case and (b) ND case. Acoustic field distributions of the acoustic plane waves impinging normally on ATS with L = 16.5λ₀ for (c) PD case and (d) ND case. Focal length (dashed-circle line for the left-hand scale) and corresponding intensity contrast |p/p₀|² (dashed-triangle line for the right-hand scale) of the ATSs as a function of L for (e) PD case and (f) ND case. The working frequency is fixed at 3.432 kHz.