Quantum noise limits in white-light-cavity-enhanced gravitational wave detectors
Quantum noise limits in white-light-cavity-enhanced gravitational wave detectors
复制标题
白光腔增强引力波探测器中的量子噪声限制
DOI：
--
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
S. Shahriar
中科院分区：
文献类型：
--
作者：
Minchuan Zhou;Zifan Zhou;S. Shahriar
在此之前，我们提出了一种引力波探测器，它采用了白光腔（WLC）效应，使用复合腔进行信号回收（CC-SR）。在这里，我们首先使用一个理想化的模型为负色散介质（NDM），并使用所谓的洞穴模型的相位不敏感的线性放大器，以占的量子噪声（QN）的NDM贡献，以确定在灵敏度带宽产品的增强的上限。我们计算了CC-SR设计的量子噪声限制的灵敏度曲线，发现经典分析预测的灵敏度的加宽也存在于这些曲线中，但有所减少。此外，我们发现，曲线总是停留在标准量子极限以上。为了克服这一限制，我们修改了色散，以补偿由光机共振效应产生的非线性相位变化。我们发现，与Bunanno和Chen [Phys. Rev. D 64，042006（2001）]预测的最高灵敏度结果相比，灵敏度带宽积增加的因子的上限为14。我们还提出了一个更简单的计划（WLC-SR），其中色散介质插入到SR腔。对于该方案，我们发现增强因子的上限为18。然后，我们考虑了一个明确的系统实现NDM，它利用五个能级的M配置产生增益，伴随着电磁感应透明（GEIT系统）。对于这个显式系统，我们采用严格的方法基于主方程计算的QN贡献的NDM，从而使我们能够确定的灵敏度带宽产品的增强，而不是其上限。具体而言，我们确定了一组参数的灵敏度带宽产品是由17.66的一个因素增强。
Previously, we had proposed a gravitational wave detector that incorporates the white-light-cavity (WLC) effect using a compound cavity for signal recycling (CC-SR). Here, we first use an idealized model for the negative dispersion medium (NDM) and use the so-called Caves model for a phase-insensitive linear amplifier to account for the quantum noise (QN) contributed by the NDM, in order to determine the upper bound of the enhancement in the sensitivity-bandwidth product. We calculate the quantum noise limited sensitivity curves for the CC-SR design, and find that the broadening of sensitivity predicted by the classical analysis is also present in these curves, but is somewhat reduced. Furthermore, we find that the curves always stay above the standard quantum limit. To circumvent this limitation, we modify the dispersion to compensate the nonlinear phase variation produced by the optomechanical resonance effects. We find that the upper bound of the factor by which the sensitivity-bandwidth product is increased, compared to the highest-sensitivity result predicted by Bunanno and Chen [Phys. Rev. D 64, 042006 (2001)], is ∼14. We also present a simpler scheme (WLC-SR), where a dispersion medium is inserted into the SR cavity. For this scheme, we found the upper bound of the enhancement factor to be ∼18. We then consider an explicit system for realizing the NDM, which makes use of five energy levels in M configuration to produce gain, accompanied by electromagnetically induced transparency (the GEIT system). For this explicit system, we employ the rigorous approach based on Master Equation to compute the QN contributed by the NDM, thus enabling us to determine the enhancement in the sensitivity-bandwidth product definitively rather than the upper bound thereof. Specifically, we identify a set of parameters for which the sensitivity-bandwidth product is enhanced by a factor of 17.66.