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arXiv · 1305.0066

Quantum-Limited Mirror-Motion Estimation

Kohjiro Iwasawa·Kenzo Makino·Hidehiro Yonezawa·Mankei Tsang·Aleksandar Davidovic·Elanor Huntington·Akira Furusawa
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Abstract

We experimentally demonstrate optomechanical motion and force measurements near the quantum precision limits set by the quantum Cramér-Rao bounds (QCRBs). Optical beams in coherent and phase-squeezed states are used to measure the motion of a mirror under an external stochastic force. Utilizing optical phase tracking and quantum smoothing techniques, we achieve position, momentum, and force estimation accuracies close to the QCRBs with the coherent state, while estimation using squeezed states shows clear quantum enhancements beyond the coherent-state bounds.

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Kohjiro Iwasawa, Kenzo Makino, Hidehiro Yonezawa, Mankei Tsang, Aleksandar Davidovic, Elanor Huntington, Akira Furusawa. 2013-05-01. Quantum-Limited Mirror-Motion Estimation. https://doi.org/10.1103/physrevlett.111.163602

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