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arXiv · 1603.09399

Force sensing based on coherent quantum noise cancellation in a hybrid optomechanical cavity with squeezed-vacuum injection

Ali Motazedifard·F. Bemani·M. H. Naderi·R. Roknizadeh·D. Vitali
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Abstract

We propose and analyse a feasible experimental scheme for a quantum force sensor based on the elimination of back-action noise through coherent quantum noise cancellation (CQNC) in a hybrid atom-cavity optomechanical setup assisted with squeezed vacuum injection. The force detector, which allows for a continuous, broad-band detection of weak forces well below the standard quantum limit (SQL), is formed by a single optical cavity simultaneously coupled to a mechanical oscillator and to an ensemble of ultracold atoms. The latter acts as a negative-mass oscillator so that atomic noise cancels exactly the back-action noise from the mechanical oscillator due to destructive quantum interference. Squeezed vacuum injection enforces this cancellation and allows to reach sub-SQL sensitivity in a very wide frequency band, and at much lower input laser powers.

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Ali Motazedifard, F. Bemani, M. H. Naderi, R. Roknizadeh, D. Vitali. 2016-06-08. Force sensing based on coherent quantum noise cancellation in a hybrid optomechanical cavity with squeezed-vacuum injection. https://doi.org/10.1088/1367-2630%2F18%2F7%2F073040

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