Laser Power Stabilization beyond the Shot Noise Limit Using Squeezed Light.
Laser Power Stabilization beyond the Shot Noise Limit Using Squeezed Light.
复制标题
DOI：
10.1103/physrevlett.121.173601
复制
发表时间：
2018-10
影响因子：
8.6
通讯作者：
H. Vahlbruch;D. Wilken;M. Mehmet;B. Willke
中科院分区：
文献类型：
--
作者：
H. Vahlbruch;D. Wilken;M. Mehmet;B. Willke
高水平的激光功率稳定性是高精度计量应用所必需的。可实现的功率稳定性的经典极限由用于产生功率控制信号的光的散粒噪声确定。增加被检测光的功率可以降低相对散粒噪声水平，并允许更高的稳定性。然而，足够高的功率并不总是可用的，高激光功率的检测是具有挑战性的。在这里，我们演示了一种在不增加检测功率的情况下提高可实现的功率稳定性的非经典方法。通过注入压缩真空场，在5~80 kHz的傅里叶频率范围内，将经典激光的功率稳定度提高了9.4-0.6分贝，超过了散粒噪声极限。对于仅90.6μA的探测光电流，我们获得了相对激光功率噪声为2.0-0.1}^+0.1}×10^-8}/Sqrt[Hz]。这是第一次演示了压缩光增强激光功率稳定，其性能相当于在经典方案中检测到的激光功率几乎增加了10倍。分析表明，该技术有可能达到4.2×10~(-10)/平方赫兹的稳定水平，在单个光电探测器上测得的光电流为58 mA。
High levels of laser power stability are necessary for high precision metrology applications. The classical limit for the achievable power stability is determined by the shot noise of the light used to generate a power control signal. Increasing the power of the detected light reduces the relative shot noise level and allows higher stabilities. However, sufficiently high power is not always available and the detection of high laser powers is challenging. Here, we demonstrate a nonclassical way to improve the achievable power stability without increasing the detected power. By the injection of a squeezed vacuum field of light we improve the classical laser power stability beyond its shot noise limit by 9.4_{-0.6}^{+0.6} dB at Fourier frequencies between 5 and 80 kHz. For only 90.6 μA of detected photocurrent we achieve a relative laser power noise of 2.0_{-0.1}^{+0.1}×10^{-8}/sqrt[Hz]. This is the first demonstration of a squeezed light-enhanced laser power stabilization and its performance is equivalent to an almost tenfold increase of detected laser power in a classical scheme. The analysis reveals that the technique presented here has the potential to achieve stability levels of 4.2×10^{-10}/sqrt[Hz] with 58 mA photocurrent measured on a single photodetector.