Quantum Optics and Optomechanics: From Fundamental Tests To Quantum Tools of the Future

该奖项支持相对论和相对论天体物理学的研究，并阐述了美国国家科学基金会“宇宙之窗”大构想的优先领域。量子力学是用来解释微观原子和亚原子尺度世界的物理学分支。量子行为本质上不同于人类对宏观世界的体验。量子系统的特点包括基本的不确定性和纠缠。这些量子现象可以用来对物理量进行更精确的测量。例如，量子工程使科学家能够测量引力波探测器(GWD)的反射镜之间的距离，精度低于attometer。该项目涉及一项正在进行的实验计划，该计划旨在开发量子系统来探测基本量子现象，以及应用于精确的量子噪声限制测量。该研究小组的重点是理解和操纵GWDS中的量子噪声，这对于提高GWDS的性能以及在宏观尺度上探索基本的量子现象(如压缩和纠缠)都是重要的。多样性是拟议工作的科学和人员方面的基础。科学多样性源于拟议研究的必然跨学科性质：它将量子光学、光学机械和量子测量科学的技术和形式主义与GWDS结合在一起。人员多样性是国际学生联合会故意招募妇女和少数族裔学生的结果(她本人也是多个少数群体的成员)，通过她自己的努力以及LIGO实验室和麻省理工学院的外联计划。此外，量子科学很受学生欢迎(该研究项目已衍生出十几篇博士和本科生论文)，并引起了公众相当大的热情。拟议的实验项目旨在研究量子涨落的多种表现及其对光学测量和宏观物体运动的影响。这允许测试量子力学的基本原理，也允许在光学传感和精确力和位置测量的量子技术方面取得进展。该小组正在进行两项利用光的量子涨落和机械运动的实验。其中一个实验探索了光学机械系统中的量子效应，在该系统中，光和机械运动之间的辐射-压力相互作用被设计为占主导地位。在这个研究项目中，使用跨越纳克到千克尺度的机械振荡器的腔光学力学实验是突出的特点，在该研究计划中，光和机械运动之间的相互作用被用来产生和操纵量子态。这些实验已经成功地展示了用于宏观反射镜的光学冷却和陷阱技术，使得能够直接观察和躲避作为先进LIGO的主要限制噪声源的量子辐射压力(Backaction)噪声，以及产生宽带光机械压缩作为一种很有前途的替代方法来产生适用于未来GW探测器的光的压缩态。这个光机械平台的一个重要特征是，它被设计成通过宏观机械振荡器实现量子区域，这些宏观机械振荡器没有低温预冷。目前的下一个目标是观察在通往创造作为室温光学机械平台一部分的反射镜的量子态的道路上的有条件压缩的机械状态。另一项实验推进了用于精密测量的压缩光技术。具体地说，该团队正在研究一种基于非线性光学材料的紧凑型压缩光源，该光源将用于研究和减少线性光学放大过程中的量子噪声，并将成为最终实现芯片上压缩器的垫脚石。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This award supports research in relativity and relativistic astrophysics, and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Quantum mechanics is the branch of physics used to explain the microscopic atomic and subatomic scale world. Quantum behavior is inherently different than the human experience of the macroscopic world. Hallmarks of quantum systems include fundamental uncertainty and entanglement. These quantum phenomena can be exploited to make more precise measurements of physical quantities. For example, quantum engineering allows scientists to measure the distance between the mirrors of a gravitational wave detector (GWD) with sub-attometer precision. This project pertains to an ongoing experimental program to develop quantum systems to probe fundamental quantum phenomena, as well as for applications to precision quantum noise-limited measurement. The emphasis of the research group is understanding and manipulating quantum noise in GWDs, which is important both for improved performance of GWDs, and also for probing fundamental quantum phenomena such as squeezing and entanglement on macroscopic scales. Diversity underpins the scientific and personnel aspects of the proposed work. The scientific diversity arises from the necessarily cross-disciplinary nature of the proposed research: it combines the techniques and formalism of quantum optics, optomechanics, and quantum measurement science with GWDs. The personnel diversity is the outcome of deliberate recruitment of women and minority students by the PI (herself a member of multiple minority groups), through her own efforts as well as those of the outreach programs of the LIGO Laboratory and MIT. Additionally, quantum science is popular with students (over a dozen Ph.D. and undergraduate theses have derived from this research program), and generates considerable enthusiasm with the public as well.The proposed experimental program aims to study multiple manifestations of quantum fluctuations and their effect on optical measurements and on motion of macroscopic objects. This allows for testing fundamental tenets of quantum mechanics, and also for making advances in quantum technologies for optical sensing and precision force and position measurement. The group is carrying out two experiments that exploit quantum fluctuations of light and mechanical motion. One experiment explores quantum effects in optomechanical systems where the radiation-pressure interaction between light and mechanical motion is engineered to dominate. Cavity optomechanics experiments with mechanical oscillators spanning nanogram- to kilogram-scales have featured prominently in this research program, where the interaction between light and mechanical motion is used to generate and manipulate quantum states. These experiments have successfully demonstrated optical cooling and trapping techniques for macroscopic mirrors, have enabled direct observation and evasion of quantum radiation pressure (backaction) noise that is a major limiting noise source in Advanced LIGO, and generation of broadband optomechanical squeezing as a promising alternative method for generating squeezed states of light suitable for future GW detectors. An important feature of this optomechanics platform is that it is designed to achieve the quantum regime with macroscopic mechanical oscillators that are not cryogenically pre-cooled. The immediate next goals are to observe conditionally squeezed mechanical states on the path toward creating quantum states of mirrors that are part of a room temperature optomechanics platform. The other experiment advances squeezed light technology for precision measurement. Specifically, the group is working on a compact squeezed light source based on nonlinear optical materials that is to be used to study and reduce quantum noise in linear optical amplification processes, and will be a steppingstone to an eventual squeezer-on-a-chip.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.