Broadband high-quality airy beams via lossy acoustic gradient-index metasurfaces

Abstract In this study, we show that fine manipulation of sound waves can be achieved through lossy acoustic gradient-index metasurfaces by utilizing the energy losses. This work, provides a practical route for achieving independent and arbitrary modulation of the amplitude and phase of sound. We demonstrate this mechanism by producing broadband high-quality airy beams. Furthermore, we realize the multifocal focusing based on this lossy acoustic gradient-index metasurfaces. Our findings increase the freedom and flexibility of the control of sound transmission.