title: Laser-rate-equation description of optomechanical oscillators.
abstract: We develop a set of laser rate equations that accurately describes mechanical amplification in optomechanical oscillators driven by photothermal or radiation pressure forces. In the process we introduce a set of parameters describing gain, stored energy, slope efficiency, and saturation power of the mechanical laser. We identify the three-phonon parametric interactions as a microscopic mechanism enabling self-oscillation. Our theory shows remarkable agreement with our experimental data, demonstrating that optomechanical self-oscillation is essentially a "phonon lasing" process in which an optical pump generates coherent acoustic phonons.
authors.affiliation: Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Khurgin
authors.forename: M W
authors.initials: MW
authors.lastname: Pruessner
authors.forename: T H
authors.initials: TH
authors.lastname: Stievater
authors.forename: W S
authors.initials: WS
authors.lastname: Rabinovich