声学Pancharatnam-Berry几何相位
Acoustic Pancharatnam-Berry Geometric Phase
AI总结：
本研究突破声波无旋纵波特性的限制，首次在理论和实验上证明非均匀声波中可存在Pancharatnam-Berry几何相位，揭示其Janus特性并实现声学超表面、声学q板等应用，为声场操控提供新途径。
摘要：
几何相位为理解量子与经典物理中的各类现象提供了统一框架。源于光学横向偏振变化的Pancharatnam-Berry（PB，潘查拉特纳姆-贝里）几何相位，已彻底改变了光操控技术。然而，由于声波具有无旋的纵波特性，该相位从未在声波中被观测到。本文从理论和实验上证明，PB相位可普遍出现在具有速度场偏振演化的非均匀声波中。以表面声波为例，我们揭示了由自旋-动量锁定导致的PB相位的奇特Janus（双面）特性，并实现了可用于多功能波前操控的声学PB超表面。我们进一步将该机制拓展至自由空间结构化声波，实现了声学q板，可通过自旋-轨道相互作用产生声学涡旋。本研究为声波特性研究提供了新见解，并使得借助PB相位操控非均匀声场成为可能，在声学通信和成像领域具有潜在应用价值。
英文摘要：
Geometric phases provide a unified framework for understanding diverse phenomena in quantum and classical physics. The Pancharatnam-Berry (PB) geometric phase, arising from variation of optical transverse polarization, has transformed light manipulation. However, this phase has never been observed in sound waves due to their curl-free longitudinal nature. Here, we theoretically and experimentally demonstrate that the PB phase can emerge in general inhomogeneous sound waves with polarization evolution of velocity field. Using surface sound waves as an example, we uncover the intriguing Janus property of the PB phase arising from spin-momentum locking, and realize acoustic PB metasurfaces for versatile wavefront manipulation. We further extend the mechanism to free-space structured sound and realize acoustic $q$-plate for generating acoustic vortices through spin-orbit interaction. Our work provides new insights into sound wave properties and enables the manipulation of inhomogeneous acoustic fields via the PB phase, with potential applications in acoustic communications and imaging.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
