A short walk through quantum optomechanics

Abstract

A short walk through quantum optomechanics P. MeystreThis paper gives an brief review of the basic physics of quantum optomechanics and provides an overview of some of its recent developments and current areas of focus. It first outlines the basic theory of cavity optomechanical cooling and gives a brief status report of the experimental state-of-the-art. It then turns to the deep quantum regime of operation of optomechanical oscillators and cover selected aspects of quantum state preparation, control and characterization, including mechanical squeezing and pulsed optomechanics. This is followed by a discussion of the "bottom-up" approach that exploits ultracold atomic samples instead of nanoscale systems. It concludes with an outlook that concentrates largely on the functionalization of quantum optomechanical systems and their promise in metrology applications. IntroductionBroadly speaking, quantum optomechanics provides a universal tool to achieve the quantum control of mechanical motion [1]. It does that in devices spanning a vast range of parameters, with mechanical frequencies from a few Hertz to GHz, and with masses from 10 −20 g to several kilos. At a fundamental level, it offers a route to determine and control the quantum state of truly macroscopic objects and paves the way to experiments that may lead to a more profound understanding of quantum mechanics; and from the point of view of applications, quantum optomechanical techniques in both the optical and microwave regimes will provide motion and force detection near the fundamental limit imposed by quantum mechanics. While many of the underlying ideas of quantum optomechanics can be traced back to the study of gravitational wave detectors in the 1970s and 1980s [2,3], the spectacular developments of the last few years rely largely on two additional developments: From the top down, it is the availability of advanced micromechanical and nanomechanical devices capable of probing extremely tiny forces, often with spatial resolution at the atomic scale. And from the bottom-up, we have gained a detailed understanding of the mechanical effects of light and how they can be exploited in laser trapping and cooling. These developments open a path to the realization of macroscopic mechanical systems that operate deep in the quantum regime, with no significant thermal noise remaining.As a result, they offer both knowledge and control of the quantum state of a macroscopic object, and increased sensitivity, precision, and accuracy in the measurement of feeble forces and fields.It was Arthur Ashkin [4] who first suggested and demonstrated that small dielectric balls can be accelerated and trapped using the radiation-pressure forces associated with focused laser beams. In later experiments these particles, weighting on the order of a microgram, were levitated against the Earth gravitational field. This advance led to the realization of optical tweezers, whose applications in biological science have become ubiquitous. In parallel, the use of the strong enhancement prov...

Classical stochastic measurement trajectories: Bosonic atomic gases in an optical cavity and quantum measurement backaction

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Control of Fano resonances and slow light using Bose-Einstein condensates in a nanocavity

“…In parallel, cavity optomechanics [26,27] has cemented its place in the present-day photonic technology [28,29]; and serves as basic building block from quantum stateengineering to the quantum communication networks [30][31][32]. Due to the ubiquitous nature of the mechanical motion, such resonators couple with many kinds of quantum devices, that range from atomic systems to the solid-state electronic circuits [33][34][35][36].…”

Proposal for an Optomechanical Bell Test

“…Introduction.-Cavity optomechanics, which describes a mechanical oscillator controlled by an electromagnetic cavity mode via a generalized radiation pressure force, is the subject of intense research [1][2][3]. Most recent progress includes the cooling of mechanical oscillators down to the ground state [4][5][6], the readout of the mechanical position with a readout imprecision below the standard quantum limit [7] as well as optomechanical squeezing [8,9] and entanglement [10].…”