Dynamics of levitated nanospheres: towards the strong coupling regime

Abstract

The use of levitated nanospheres represents a new paradigm for the optomechanical cooling of a small mechanical oscillator, with the prospect of realising quantum oscillators with unprecedentedly high quality factors. We investigate the dynamics of this system, especially in the so-called self-trapping regimes, where one or more optical fields simultaneously trap and cool the mechanical oscillator. The determining characteristic of this regime is that both the mechanical frequency ${\omega }_M$ and single-photon optomechanical coupling strength parameters $g$ are a function of the optical field intensities, in contrast to usual set-ups where ${\omega }_M$ and $g$ are constant for the given system. We also measure the characteristic transverse and axial trapping frequencies of different sized silica nanospheres in a simple optical standing wave potential, for spheres of radii $r=20-500$\,nm, illustrating a protocol for loading single nanospheres into a standing wave optical trap that would be formed by an optical cavity. We use this data to confirm the dependence of the effective optomechanical coupling strength on sphere radius for levitated nanospheres in an optical cavity and discuss the prospects for reaching regimes of strong light-matter coupling. Theoretical semiclassical and quantum displacement noise spectra show that for larger nanospheres with $r\gtrsim 100$\,nm a range of interesting and novel dynamical regimes can be accessed. These include simultaneous hybridization of the two optical modes with the mechanical modes and parameter regimes where the system is bistable. We show that here, in contrast to typical single-optical mode optomechanical systems, bistabilities are independent of intracavity intensity and can occur for very weak laser driving amplitudes.

References in corpus (14)

• Sideband Cooling Micromechanical Motion to the Quantum Ground State
• Strong dispersive coupling of a high finesse cavity to a micromechanical membrane
• Quantum Theory of Cavity-Assisted Sideband Cooling of Mechanical Motion
• Theory of ground state cooling of a mechanical oscillator using dynamical back-action
• Observation of strong coupling between a micromechanical resonator and an optical cavity field
• Radiation-pressure cooling and optomechanical instability of a micro-mirror
• Self-cooling of a micro-mirror by radiation pressure
• Circuit cavity electromechanics in the strong coupling regime
• Cooling a nanomechanical resonator with quantum back-action
• Millikelvin cooling of an optically trapped microsphere in vacuum
• Dispersive optomechanics: a membrane inside a cavity
• Quantum Optomechanics - throwing a glance
• Optically Levitating Dielectrics in the Quantum Regime: Theory and Protocols
• Master equation approach to optomechanics with arbitrary dielectrics

Cited by in corpus (31)

• Cavity cooling of an optically levitated nanoparticle
• Cavity cooling a single charged nanoparticle
• Optomechanics with Levitated Particles
• Nanoscale temperature measurements using non-equilibrium Brownian dynamics of a levitated nanosphere
• Large quantum superpositions of a levitated nanodiamond through spin-optomechanical coupling
• Optomechanics of Levitated Dielectric Particles
• Nonlinear dynamics and millikelvin cavity-cooling of levitated nanoparticles
• Tunable fast and slow light in a hybrid optomechanical system
• Testing Wavefunction Collapse Models using Parametric Heating of a Trapped Nanosphere
• Testing collapse models with levitated nanoparticles: the detection challenge
• Optical trapping and control of nanoparticles inside evacuated hollow core photonic crystal fibers
• Opto-Nanomechanics Strongly Coupled to a Rydberg Superatom: Coherent vs. Incoherent Dynamics
• Selectable linear or quadratic coupling in an optomechanical system
• Quantum cooling and squeezing of a levitating nanosphere via time-continuous measurements
• Control of Fano resonances and slow light using Bose-Einstein condensates in a nanocavity
• Quantum displacement sensing and cooling in 3D levitated cavity optomechanics
• Auxiliary-cavity-assisted ground-state cooling of optically levitated nanosphere in the unresolved-sideband regime
• Coherent scattering 2D cooling in levitated cavity optomechanics
• Quadratic optomechanical cooling of a cavity-levitated nanosphere
• Optical forces and torques on eccentric nanoscale core-shell particles
• Split-sideband spectroscopy in slowly modulated optomechanics
• General solution of the time evolution of two interacting harmonic oscillators
• Non-classicality of optomechanical devices in experimentally realistic operating regimes
• Theory of Optomechanical Interactions in Superfluid He
• Levitated optomechanics with a fiber Fabry-Perot interferometer
• In-situ tuning of whispering gallery modes of levitated silica microspheres
• Non-Hermitian physics of levitated nanoparticle array
• Nonclassical states of levitated macroscopic objects beyond the ground state
• Employing coupled cavities to increase the cooling rate of a levitated nanosphere in the resolved sideband regime
• Is there charged dark matter bound to ordinary matter? Can it produce observable quantum effects?
• Bayesian optimization of non-classical optomechanical correlations