A single acoustic metamaterial with multifunctional use is highly needed for various applications. Herein, a bifunctional acoustic metamaterial for beam switching between the focusing beam and bottle beam is demonstrated, which consists of a groove structure for binary phases and a partitioned piezoelectric transducer (p-PZT) for incident wavefront modulation. The p-PZT is divided into inner and outer regions for selective excitation, and the focusing beam and bottle beam can be switched in real-time by applying different exciting signals on the p-PZT. Theoretical calculation, numerical simulation, and experimental measurement are conducted to verify the effectiveness of the proposed bifunctional acoustic metamaterial for beam switching. Furthermore, the focal plane of both the focusing beam and bottle beam can be linearly tuned by the operating frequency. This work may find potential applications in medical ultrasonic therapy, sound printing, and biological particle manipulation.

中文翻译：

---

用于双相和选择性激发光束切换的双功能声学超材料

各种应用都非常需要一种具有多功能用途的单一声学超材料。在此，展示了一种用于聚焦光束和瓶形光束之间的光束切换的双功能声学超材料，它由用于二元相的凹槽结构和用于入射波前调制的分区压电换能器（p-PZT）组成。p-PZT分为内部区域和外部区域进行选择性激发，通过在p-PZT上施加不同的激发信号可以实时切换聚焦光束和瓶形光束。通过理论计算、数值模拟和实验测量验证了所提出的双功能声学超材料用于光束切换的有效性。此外，聚焦光束和瓶光束的焦平面都可以通过工作频率进行线性调谐。这项工作可能会在医学超声治疗、声音打印和生物粒子操纵方面找到潜在的应用。