Anomalous Reflection of Acoustic Waves in Air with Metasurfaces at Low Frequency

Figure 4

Acoustic axicon realized by the designed planar metasurface. (a) The normalized squared absolute pressure distribution of the reflected waves. The red arrow indicates the propagation direction of incident wave. (b) Transient sound pressure field distribution of reflected wave. The black arrows refer to the reflected directions. The angle between equiphase surface and -axis is 10°. (c) The longitudinal distribution of acoustic intensity at . (d) The transverse distribution of acoustic intensity at = 8500 mm.

(a)

(b)

(c)

(d)