Arnold Sommerfeld Center for Theoretical Physics, Center for NanoScience and Department of Physics, Ludwig-Maximilians-Universität at München, Theresienstrasse 37, 80333 Munich, Germany.
Phys Rev Lett. 2012 Dec 21;109(25):253601. doi: 10.1103/PhysRevLett.109.253601. Epub 2012 Dec 18.
In the past few years, coupling strengths between light and mechanical motion in optomechanical setups have improved by orders of magnitude. Here we show that, in the standard setup under continuous laser illumination, the steady state of the mechanical oscillator can develop a nonclassical, strongly negative Wigner density if the optomechanical coupling is comparable to or larger than the optical decay rate and the mechanical frequency. Because of its robustness, such a Wigner density can be mapped using optical homodyne tomography. This feature is observed near the onset of the instability towards self-induced oscillations. We show that there are also distinct signatures in the photon-photon correlation function g(2)(t) in that regime, including oscillations decaying on a time scale not only much longer than the optical cavity decay time but even longer than the mechanical decay time.
在过去的几年中，光机械装置中的光与机械运动之间的耦合强度已经提高了几个数量级。在这里，我们表明，如果光机械耦合与光衰减率和机械频率相当或更大，则在连续激光照射下的标准设置中，机械振荡器的稳态可以发展出非经典的、强烈的负维格纳密度。由于其稳健性，可以使用光学同调断层扫描来映射这种维格纳密度。这种特性在向自诱导振荡的不稳定性开始时附近可以观察到。我们表明，在该区域中，光子-光子相关函数 g(2)(t)中也存在明显的特征，包括在时间尺度上衰减的振荡，其时间尺度不仅比光学腔衰减时间长得多，甚至比机械衰减时间还要长。
