Atomic Ensembles Entangled by Light for Measurements Below the Standard Quantum Limit

光纠缠的原子系综用于低于标准量子极限的测量

• 批准号: 1205554
• 负责人: Vladan Vuletic
• 金额: $ 45万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1205554&HistoricalAwards=false
• 关键词: Atomic; Ensembles; Entangled; Light; Measurements; Atomic; Ensembles; Entangled; Light; Measurements

Entangled states of atomic ensembles have the potential to overcome various limits in quantum measurements, including the so-called standard quantum limit associated with measurements on a collection of independent particles. To realize entanglement in a many-body system, internal states of cold, trapped atoms that are strongly coupled to laser light inside an optical resonator will be used. The photons inside the cavity act as messengers between distant atoms, and can be used to induce effective state-dependent long-range atom-atom interactions. These interactions, in turn, can be utilized to redistribute quantum noise so as to enhance the signal-to-noise ratio of atomic clocks and atom interferometers ("spin squeezing"). In this project we implement a modified spin squeezing method that allows one to disentangle the outgoing light from the atoms while maintaining the light-mediated atom-atom interaction. This new method provides not only much stronger spin squeezing than previously possible, it also enables the generation of non-Gaussian entangled states and even Schroedinger cat states in mesoscopic atomic ensembles. Furthermore, using the strong interaction between an atom and a mode of the optical resonator, we hope to demonstrate a variety of novel quantum optical devices, including a single-photon all-optical switch, a dispersive photon-number-state filter, and a deterministic quantum gate between two photons.A major frontier of physics is the control of quantum mechanical many-body systems. Such control will enable novel devices for storing and processing quantum information, improve fundamental precision measurements, and enhance and deepen our understanding of key concepts of many-body quantum physics. Of particular interest is the quantum control of precision systems such as atomic clocks. Atomic clocks are the most accurate devices ever made by mankind, and have many important technological applications, including the Global Positioning System and telecommunication networks. This research program could significantly improve the precision of optical-transition atomic clocks beyond current limits, and enable many new technologies linked to the ability to precisely keep time. The project will train graduate students and undergraduate students. Exceptional high-school students will be integrated into the research effort. Efforts are made to include underrepresented minority students.

原子集合的纠缠状态有可能克服量子测量的各种限制，包括与独立颗粒集合相关的所谓标准量子限制。为了在多体系统中实现纠缠，将使用强烈耦合到光学谐振器内部的寒冷，被困的原子的内部状态。腔内的光子作为遥远原子之间的使者，可用于诱导有效的状态依赖性远程原子 - 原子相互作用。反过来，这些相互作用可用于重新分布量子噪声，从而增强原子钟和原子干涉仪的信噪比（“旋转挤压”）。 在这个项目中，我们实施了一种修改的自旋挤压方法，该方法使人们可以在保持光介导的原子-ATOM相互作用的同时将其从原子中解散。这种新方法不仅提供了比以前可能更强大的旋转挤压，还可以使非高斯纠缠状态甚至施罗辛格猫在介观原子综合体中产生。 此外，使用原子和光学谐振器模式之间的牢固相互作用，我们希望展示各种新型的量子光学设备，包括单光子全光开关，分散光子数字滤波器和确定性的量子元素的分散量子量，并在两个光光子之间进行确定性的量子。这种控制将使新的设备能够存储和处理量子信息，改善基本精确度测量，并增强和加深我们对多体量子物理学的关键概念的理解。特别感兴趣的是精确系统（例如原子钟）的量子控制。 原子钟是人类有史以来最准确的设备，并具有许多重要的技术应用，包括全球定位系统和电信网络。该研究计划可以显着提高当前限制之外的光学转换原子时钟的精度，并启用许多与精确保持时间能力相关的新技术。 该项目将培训研究生和本科生。杰出的高中生将纳入研究工作。 努力包括代表性不足的少数民族学生。