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arXiv · 1606.07377

Split-sideband spectroscopy in slowly modulated optomechanics

E. B. Aranas·P. G. Z. Fonseca·P. F. Barker·T. S. Monteiro
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Abstract

Optomechanical coupling between the motion of a mechanical oscillator and a cavity represents a new arena for experimental investigation of quantum effects on the mesoscopic and macroscopic scale.The motional sidebands of the output of a cavity offer ultra-sensitive probes of the dynamics. We introduce a scheme whereby these sidebands split asymmetrically and show how they may be used as experimental diagnostics and signatures of quantum noise limited dynamics. We show split-sidebands with controllable asymmetry occur by simultaneously modulating the light-mechanical coupling $g$ and $\omega_M$ - slowly and out of-phase. Such modulations are generic but already occur in optically trapped set-ups where the equilibrium point of the oscillator is varied cyclically. We analyse recently observed, but overlooked, experimental split-sideband asymmetries; although not yet in the quantum regime, the data suggests that split sideband structures are easily accessible to future experiments.

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E. B. Aranas, P. G. Z. Fonseca, P. F. Barker, T. S. Monteiro. 2016-06-23. Split-sideband spectroscopy in slowly modulated optomechanics. https://doi.org/10.1088/1367-2630/18/11/113021

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