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arXiv · 1601.01663

Measurement-induced macroscopic superposition states in cavity optomechanics

Ulrich B. Hoff·Johann Kollath-Bönig·Jonas S. Neergaard-Nielsen·Ulrik L. Andersen
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Abstract

We present a novel proposal for generating quantum superpositions of macroscopically distinct states of a bulk mechanical oscillator, compatible with existing optomechanical devices operating in the readily achievable bad-cavity limit. The scheme is based on a pulsed cavity optomechanical quantum non-demolition (QND) interaction, driven by displaced non-Gaussian states, and measurement-induced feedback, avoiding the need for strong single-photon optomechanical coupling. Furthermore, we show that single-quadrature cooling of the mechanical oscillator is sufficient for efficient state preparation, and we outline a three-pulse protocol comprising a sequence of QND interactions for squeezing-enhanced cooling, state preparation, and tomography.

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Ulrich B. Hoff, Johann Kollath-Bönig, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen. 2016-01-07. Measurement-induced macroscopic superposition states in cavity optomechanics. https://doi.org/10.1103/physrevlett.117.143601

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