Acoustic Waves Remotely Control Material Stiffness

Researchers demonstrate how sound can move "kinks" within materials to tune their softness or firmness.

Mar. 19, 2026 at 12:58am

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A research team including members from the University of Michigan has shown that specific frequencies of acoustic waves can reliably move localized features in a material known as mechanical kinks, which determine whether different regions of the material are soft or stiff. This could lead to materials whose properties can be remotely tuned using vibrations.

Why it matters

This breakthrough could enable future technologies where the internal configurations and functionalities of materials can be adjusted on-demand without physically modifying them. It opens up possibilities for adaptive structures and devices that can change their stiffness or other mechanical properties in response to external stimuli.

The details

The researchers used theoretical, computational, and physical models to demonstrate how sound waves can control the movement of mechanical kinks - boundaries between distinct internal states of a material that determine its deformation. By sending short pulses of acoustic waves, they were able to predictably move the kinks step-by-step, effectively flipping which regions of the material were soft or stiff. This was achieved in a modeled metamaterial without energy barriers that typically pin kinks in place.

  • The research was published in the journal Nature Communications in 2026.

The players

Xiaoming Mao

Professor of physics at the University of Michigan and leader of the U-M cohort working on the study.

Nicholas Boechler

Associate professor of mechanical and aerospace engineering at the University of California San Diego and co-author of the study.

Kai Sun

Professor of physics at the University of Michigan and part of the research team.

Georgios Theocharis

CNRS scientist and team lead at the Laboratory of Acoustics at Le Mans University.

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What they’re saying

“This opens the door to future technologies where you can remotely tune configurations and functionalities deep inside a material without cutting it open.”

— Xiaoming Mao, Professor of physics

“You can send a small pulse, and the kink moves a little. Send another pulse, and it moves a little more. It's basically a remote control for the material's internal state.”

— Nicholas Boechler, Associate professor of mechanical and aerospace engineering

What’s next

The research team is continuing to explore the phenomenon of kink behavior in more disordered metamaterials.

The takeaway

This breakthrough in using sound waves to remotely control a material's internal structure and stiffness could enable a new class of adaptive and responsive materials and devices with tunable mechanical properties.