Direct Amplification of Sound By Light

TL;DR

The paper introduces the opto-acoustic parametric amplifier (OAPA), a device that amplifies sound directly using light through radiation pressure, with applications in amplification and cooling to quantum ground state.

Contribution

It presents a novel opto-acoustic device analogous to optical parametric amplifiers, enabling direct sound amplification and quantum ground state cooling.

Findings

OAPA can amplify acoustic signals directly.

OAPA can cool acoustic resonators to quantum ground state.

The device operates in tunable regimes for amplification and cooling.

Abstract

A new device, the opto-acoustic parametric amplifier (OAPA), is introduced, which is analogous to an optical parametric amplifier (OPA). The radiation pressure reaction of light on the reflective surface of an acoustic resonator provides nonlinearity similar to the Kerr effect in the OPA. The OAPA can be tuned to operate in two regimes. In the positive gain regime, an acoustic signal is directly amplified. In the negative gain regime, we show that the acoustic resonator can be cooled to the quantum ground state.