Torsional Mechanical Oscillator Driven by the Orbital Angular Momentum of Sound

Benjamin Sanchez-Padilla (1) , Etienne Brasselet (1)

1 LOMA - Laboratoire Ondes et Matière d'Aquitaine

We demonstrate that the orbital angular momentum of radiating waves can be used to drive a mechanical oscillator, an option that has remained elusive to date on experimental grounds whatever the nature of the waves. This is done using an amplitude-modulated ultrasonic wave interacting with a centimeter-size torsional pendulum. Achieved resonant quantitative measurements of the acoustic radiation torque and material properties set the basis for orbital-angular-momentum-based metrology applications and possibly cooling of the rotational degree of freedom of macroscopic objects.

Domaines: Physique [physics]; Acoustique [physics.class-ph]; Mécanique des structures [physics.class-ph]; Physique Classique [physics.class-ph]

Benjamin Sanchez-Padilla, Etienne Brasselet. Torsional Mechanical Oscillator Driven by the Orbital Angular Momentum of Sound. Physical Review Applied, 2020, 13 (6), ⟨10.1103/PhysRevApplied.13.064069⟩. ⟨hal-02894592⟩