Materials science

Capacitance

Wave propagation

Physics

Electrode

Phase modulation

Piezoelectricity

Lamb waves

Optics

Acoustics

Quantum mechanics

Vibration

Refraction

Computer science

Computer graphics (images)

Modulation (music)

Wavefront

Phase noise

Planar

Applied Physics Letters

This letter reports designs of adaptive metasurfaces capable of modulating incoming wave fronts of elastic waves through electromechanical-tuning of their cells. The proposed elastic metasurfaces are composed of arrayed piezoelectric units with individually connected negative capacitance elements that are online tunable. By adjusting the negative capacitances properly, accurately formed, discontinuous phase profiles along the elastic metasurfaces can be achieved. Subsequently, anomalous refraction with various angles can be realized on the transmitted lowest asymmetric mode Lamb wave. Moreover, designs to facilitate planar focal lenses and source illusion devices can also be accomplished. The proposed flexible and versatile strategy to manipulate elastic waves has potential applications ranging from structural fault detection to vibration/noise control.

Tunable modulation of refracted lamb wave front facilitated by adaptive elastic metasurfaces