Quantum back-action in measurements of zero-point mechanical oscillations
Quantum back-action in measurements of zero-point mechanical oscillations
复制标题
零点机械振荡测量中的量子反作用
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
Yanbei Chen
中科院分区：
文献类型：
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作者：
F. Khalili;H. Miao;Huan Yang;A. Safavi;O. Painter;Yanbei Chen
测量导致的反作用是海森堡不确定性原理的一个直接结果，是量子测量的决定性特征。我们利用量子测量理论分析了萨法维 - 奈尼等人近期的实验[《物理评论快报》108卷，033602（2012年）]，并且表明该实验的结果不仅表征了近基态纳米机械振子的零点涨落，还通过传感噪声和反作用噪声之间存在的相关性证明了量子反作用噪声的存在。这些相关性源于机械振子和测量装置之间的量子相干性，这种相干性在测量过程中建立起来，并且是将灵敏度提高到超越标准量子极限的关键。
Measurement-induced back-action, a direct consequence of the Heisenberg uncertainty principle, is the defining feature of quantum measurements. We use quantum measurement theory to analyze the recent experiment of Safavi-Naeini et al. [Phys. Rev. Lett. 108 033602 (2012)], and show that the results of this experiment not only characterize the zero-point fluctuation of a near-ground-state nanomechanical oscillator, but also demonstrate the existence of quantum back-action noise—through correlations that exist between sensing noise and back-action noise. These correlations arise from the quantum coherence between the mechanical oscillator and the measuring device, which build up during the measurement process, and are key to improving sensitivities beyond the standard quantum limit.