Ultra-stable Cryogenic Nanopositioner for Quantum Optomechanics and Zeptonewton Force Sensing

我们研究计划的中心目标是实现由激光驱动和增强的超灵敏机械系统。最近，我们的团队取得了重大突破，制造出了约50纳米薄的“微型蹦床”，在室温下表现出世界纪录的力灵敏度（噪声底限以牛顿为单位，或相当于相隔约100公里的两个人之间的引力）。同时，这些设备实现了非常低的光学损耗，使它们与世界上最灵敏的干涉仪兼容，用于光学力学实验。特别是，所证明的参数对应于这样一种情况，即光在单个干涉仪光子水平上施加的力（平均）将深刻地影响机械轨迹。

The central aim of our research program is to realize ultrasensitive mechanical systems that are actuated and enhanced by laser light. Recently, our group made a major breakthrough, fabricating ~50-nanometer-thin "micro-trampolines" exhibiting world-record force sensitivity at room temperature (with a noise floor measured in attonewtons, or equivalent to the gravitational pull between two people separated by ~100 km). At the same time, these devices achieve extraordinarily low optical losses, making them compatible with the world's most sensitive interferometers for optomechanics experiments. In particular, the demonstrated parameters correspond to a situation in which the forces exerted by light at the level of a single interferometer photon (on average) will profoundly affect the mechanical trajectory. The performance of these and related optomechanical systems will improve by orders of magnitude at cryogenic (millikelvin) temperatures, due to a combination of reduced thermal force noise and increased mechanical quality factor. The resulting unprecedented mechanical coherence will enable a host of exciting optomechanics experiments operating deeply within the regime of macroscopic quantum motion, as well as the development of new quantum information transduction platforms and force sensing at the level of ~10 zeptonewtons, wherein a variety of goals (e.g. nanometer-resolution magnetic resonance imaging) become feasible. Our group already has access to a CFI-funded dilution cryostat, but in order to achieve these extraordinarily sensitive goals, a stable, vibration-isolated, encoded cryogenic nanopositioner is an absolute requirement.