Quantum-Enhanced Optomechanical Accelerometers

利用光来测量和操纵机械物体最近在量子光学力学领域取得了巨大的进展。 现在可以使用光学腔内的辐射压力将宏观机械谐振器冷却到接近绝对零度。 相反，通过将激光场反射出低损耗的机械谐振器，可以将其统计波动“挤压”到经典极限之外，从而为量子增强干涉测量提供资源。该项目将联合收割机这两种技术相结合，开发下一代光机械惯性传感器，其中光被用来探测响应加速参考系的机械谐振器的位移。 除了天基重力测量和惯性导航等精密应用外，该项目还将为低于标准量子极限的加速度测量和将加速度校准为基本常数等基础实验打开大门。该项目的长期目标是开发一种新型的可现场部署的小型化量子技术，具体目标是：（1）展示第一个具有纳米g灵敏度的芯片级光机械加速度计（以紧凑的外形实现诸如惯性导航和重力测量的精密应用），（2）通过在声频腔光机系统中实现有质动力光压缩，演示了一种压缩增强型光机加速度计;（3）使用辐射压力散粒噪声来将光机械加速度计校准到基本常数;以及（4）通过利用高保真相干和基于测量的反馈冷却技术，使用辐射压力来稳定光机械加速度计。为了实现这些目标，研究人员将改进两种先进的传感器设计，代表PI和co-PI的互补专业知识：（1）集成在法布里-珀罗腔中的厘米级高应力氮化硅膜和（2）与光纤腔集成的大块熔融石英光机械谐振器。 作为一种使能工具，PI/CoPI还将开发一种紧凑的激光源，能够在声频下进行散粒噪声限制操作。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The use of light to measure and manipulate mechanical objects has recently seen dramatic advances in the field of quantum optomechanics. It is now possible to cool a macroscopic mechanical resonator to near absolute zero using radiation pressure inside an optical cavity. Conversely, by reflecting a laser field off a low-loss mechanical resonator, it is possible to “squeeze” its statistical fluctuations beyond classical limits, providing a resource for quantum-enhanced interferometric measurements. This project will combine both techniques to develop next-generation optomechanical inertial sensors, in which light is used to probe the displacement of a mechanical resonator in response to accelerating reference frame. In addition to precision applications such as space-based gravimetry and inertial navigation, the project will open the door to fundamental experiments such as accelerometry below the standard quantum limit and calibration of acceleration to fundamental constants. The long-term vision is a new class of field-deployable, miniaturized quantum technology.Specific goals of the project are (1) demonstrate the first chip-scale optomechanical accelerometer with nano-g sensitivity (enabling precision applications such as inertial navigation and gravimetry in a compact form factor), (2) demonstrate a squeezing-enhanced optomechanical accelerometer by realizing ponderomotive light squeezing in an acoustic frequency cavity optomechanical system; (3) use radiation pressure shot noise to calibrate an optomechanical accelerometer to fundamental constants; and (4) use radiation pressure to stabilize an optomechanical accelerometer, by harnessing high fidelity coherent and measurement-based feedback cooling techniques. To accomplish these goals, the researchers will refine two advanced sensor designs representing complementary expertise of the PI and co-PI: (1) a centimeter-scale high stress silicon nitride membrane integrated in a Fabry-Perot cavity and (2) a bulk fused-silica optomechanical resonator integrated with a fiber cavity. As an enabling tool, the PI/CoPI will also develop a compact laser source capable of shot-noise-limited operation at acoustic frequencies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.