Active optomechanics.

Cavity optomechanics explores the coupling between optical and mechanical modes mediated by the radiation pressure force. Unlike the passive scheme, the active optomechanics with optical gain directly imposes the mechanical motion upon the lasing dynamics, unveiling the intrinsic properties determined by the system itself. Here we numerically explore the general characteristics of the active optomechanics. The effects of the mechanical oscillation on the macroscopic laser include introducing multiple unstable regimes in the lasing phase, shifting the laser central frequency, broadening the laser spectrum, and degrading the laser frequency stability. Reducing the optical gain down to one active atom highlights the quantum nature of atom–cavity and photon–phonon interactions. The one-atom optomechanical microlaser does not only emit nonclassical photons but also generate nonclassical photon–phonon pairs. Our work extends the cavity optomechanics to the active fashion, paving the way towards optomechanical light sources for photonic integrated circuits, on-chip quantum communication, and biosensing. Active optomechanics offers a route to precise microscopic sensing by measuring the intrinsic laser dynamics. Here, the principles of active optomechanics are studied numerically at the limit of a single active atom, opening a path to quantum applications. [ABSTRACT FROM AUTHOR]