A group of international scientists has developed a new way to use sound waves to create special patterns on the surface of water, allowing them to accurately control floating objects of different sizes. In laboratory tests, they generated complex topological wave structures such as vortices, Möbius like loops, and skyrmions three dimensional twisting wave patterns. These patterns can push, pull, or steer objects by using forces similar to those found in optical systems, such as gradient forces and radiation pressure. Some waves act like “invisible tweezers,” holding objects still, while others move them along circular or spiral paths. The experiments used 3D-printed structures connected to speakers that emitted low-frequency sound, which created the patterns predicted by computer simulations. Although the research is still in its early stages, it suggests many future applications. At large scales, specially shaped waves might help gather oil spills or produce energy. At tiny scales, similar ideas using light waves might allow scientists to manipulate cells for medical research. Experts note that applying this technology in the ocean will be challenging due to noise and environmental conditions, but the work lays the foundation for new ways of controlling water waves and particle movement.
Read more-https://spectrum.ieee.org/sound-waves