标题： 涡旋对舞蹈和振荡的观察 显示英文标题

标题： Observation of vortex-pair dance and oscillation

摘要： 涡旋动力学，包括涡旋的运动、演化和传播，在流体动力学、大气科学和物理学等多个领域都引起了人们的兴趣和挑战。 本研究聚焦于涡旋对场的基本动力学，这些场在光学中被称为涡旋对光束（VPBs）。 由于其独特的性质，包括涡旋的吸引和排斥，VPBs受到了越来越多的关注。 在此，我们探讨了纯相位涡旋对光束（PPVPBs）的动力学，并观察到了涡旋令人着迷的螺旋和交织行为，类似于涡旋对舞蹈。 我们发现了自由空间中PPVPBs的涡旋间距离的振荡特性。 观察到的舞蹈和振荡现象与初始涡旋间距离密切相关，并可在流体力学图景中得到很好的解释。 值得注意的是，涡旋舞蹈和振荡改变了涡旋对湮灭的过程，扩展了相反涡旋的生存范围。 这一发现增强了我们对涡旋相互作用的理解，并揭示了涡旋-涡旋和涡旋-反涡旋相互作用的复杂动力学。 显示英文摘要

摘要： Vortex dynamics, which encompass the motion, evolution, and propagation of vortices, elicit both fascination and challenges across various domains such as fluid dynamics, atmospheric science, and physics. This study focuses on fundamental dynamics of vortex-pair fields, specifically known as vortex-pair beams (VPBs) in optics. VPBs have gained increasing attention due to their unique properties, including vortex attraction and repulsion. Here, we explore the dynamics of pure-phase VPBs (PPVPBs) and observe intriguing helical and intertwined behaviors of vortices, resembling a vortex-pair dance. We uncover the oscillation property of the intervortex distance for PPVPBs in free space. The observed dancing and oscillation phenomena are intricately tied to the initial intervortex distance and can be explained well in the hydrodynamic picture. Notably, the vortex dancing and oscillation alter the process of vortex-pair annihilation, extending the survival range for opposite vortices. This discovery enhances our understanding of vortex interactions and sheds light on the intricate dynamics of both vortex-vortex and vortex-antivortex interactions.