Sound is usually something we hear, not something we touch.
But researchers at Virginia Tech have found a way to turn acoustic waves into invisible “hands” that can grab, move, and guide tiny objects on a chip.
This breakthrough could open the door to new medical tools, lab devices, and advanced electronics that work without physical contact.
The research is led by Zhenhua Tian, an assistant professor of mechanical engineering at Virginia Tech, and his team.
Their work explores how carefully shaped sound waves can be used to control fluids and microscopic particles, such as cells or blood components, directly on electronic chips. The study has been published in Nature Communications.
Acoustic waves are vibrations that travel through materials like air, water, or solids. While they are best known for carrying sound to our ears, they also carry energy.
Anyone who has seen dust bounce on a loud speaker has seen this energy in action. Tian’s team is harnessing that same principle but at a much smaller and more precise scale.
Until now, most acoustic chips relied on a standard component called an interdigital transducer, or IDT, to generate sound waves.
These devices produce mostly flat, straight waves, which are useful for simple tasks but limited when it comes to complex movement. Using those waves to manipulate tiny objects is like trying to pick up a ball with a flat palm—you can push it, but you cannot fully control it.
To solve this problem, Tian’s team designed an entirely new way to generate acoustic waves on a chip. They created a device that can produce curved, overlapping, and highly adjustable waves.
These waves can work together like fingers, allowing sound to trap particles, steer them along specific paths, or move fluids with far greater control than before.
The new chip includes redesigned electrodes and carefully engineered structures that shape how sound energy flows.
By adjusting the phase and direction of the waves, the researchers can tilt, bend, and focus sound in ways that were previously impossible on such a small platform. The result is a compact, all-in-one chip that can send powerful acoustic jets across longer distances while remaining precise.
What makes this advance especially powerful is that the chip functions as a metamaterial. Unlike ordinary materials, metamaterials are designed to control energy in unusual and highly customizable ways. In this case, the material structure allows sound waves to be reshaped for different tasks, from routing acoustic signals to manipulating fluids and particles.
The potential applications are wide-ranging. In medicine, such chips could help remove clots, separate blood components, or perform noninvasive procedures. In laboratories, they could replace centrifuges or improve biosensors. The technology may also aid in micro-scale manufacturing and even help cool electronic devices.
Tian’s team is continuing to test the chip in both liquids and solid materials. Early results suggest that sound, guided in the right way, could become a powerful new tool for handling the smallest building blocks of life and technology—without ever laying a finger on them.
