Quadratic optomechanical cooling of a cavity-levitated nanosphere
N. P. Bullier, A. Pontin, P. F. Barker
Abstract
We report on cooling of the center-of-mass motion of a nanoparticle via a coupling between its motion and the optical field within a high finesse cavity. The resulting coupling is purely quadratic in displacement and gives rise to a van der Pol nonlinear damping. These dynamics are analogous to conventional parametric feedback where the cavity provides passive feedback without an additional measurement. We show experimentally that as feedback cooling, the resulting energy distribution is strongly nonthermal and can be controlled by the nonlinear damping induced by the cavity. Our work represents a demonstration of a cavity cooling dominated by this type of coupling across all optomechanical platforms.
Topics & Concepts
FinessePhysicsCoupling (piping)Quadratic equationWork (physics)Nonlinear systemOptomechanicsDisplacement (psychology)Field (mathematics)Parametric statisticsClassical mechanicsDynamics (music)Quantum electrodynamicsMotion (physics)Nonlinear opticsEnergy (signal processing)Optical cavityEquations of motionOpticsResonatorLaser coolingQuantum mechanicsLaserDistribution (mathematics)MechanicsPhase (matter)Van der Pol oscillatorCoupled mode theoryMechanical and Optical ResonatorsForce Microscopy Techniques and ApplicationsQuantum Electrodynamics and Casimir Effect