CAREER: Matter-Wave Quantum Optics in Spin-Space in Ultracold Sodium Gases

职业：超冷钠气自旋空间中的物质波量子光学

• 批准号: 1846965
• 负责人: Arne Schwettmann
• 金额: $ 50万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1846965&HistoricalAwards=false
• 关键词: CAREER; Matter; Wave; Quantum; Optics

This project is jointly funded by the Atomic, Molecular, and Optical Physics Experiment Program, and the Established Program to Stimulate Competitive Research (EPSCoR).Collisions between atoms in gases happen all around us, for example in the air that we breathe every day. At room temperature, the collisions are random and very difficult to control. By cooling a gas to ultracold temperatures near absolute zero (below minus 273 degrees Celsius) and trapping it in the center of a vacuum chamber, collisions can be controlled and used to develop new technologies such as quantum-limited sensors for impurities. An ultracold gas behaves like a single quantum mechanical object, a matter wave. Collisions still take place in the matter wave, but they now happen in a predictable fashion. In a sodium matter wave, the collisions can be controlled precisely via microwave radiation. The colliding atoms behave like small magnets with magnetic north and south poles determined by the direction of their atomic spin. During collisions, atoms experience each other's magnetic fields and change their spin directions. As they change directions, the atomic spins become correlated with each other at the quantum level, a phenomenon known as quantum entanglement. Quantum entanglement is useful when atoms are used as sensors. All entangled atoms react to external influences in unison, increasing the sensitivity of a sensor. This research project will use controlled collisions in sodium matter waves to study quantum-enhanced sensing and other quantum technologies. This project will study the role of impurities and will also explore differences and similarities compared to experiments with entangled beams of light. The research will improve our experimental understanding of quantum technologies based on matter waves under realistic conditions, in the presence of loss and impurities. This has practical applications for development of robust quantum-enhanced sensors, for development of quantum-enhanced probes for ultracold gases, and for improving our understanding of how we can control spin in matter waves at the quantum level.The goal of this research program is to study a new generation of quantum technologies based on quantum engineering of matter-waves, such as quantum-enhanced sensors for external fields with high spatial resolution, quantum-enhanced probes of ultracold atomic samples to measure spin populations with reduced noise, and quantum-enhanced matter-wave devices such as phase-sensitive amplifiers, similar to those known from quantum optics with light. The control of matter-waves is exerted by microwave-dressing and RF control of spin-exchange collisions in a Bose-Einstein condensate of atomic sodium in the limit of long evolution times. During spin-exchange collisions in the F=1 sodium gas, pairs of atoms with magnetic quantum number m=0 collide and change into pairs with m=+/-1 and vice versa. This process generates quantum entanglement similar to four-wave mixing with light. But there are important differences in the atomic system due to extra terms in the Hamiltonian not present in the photonic system. These differences become increasingly important for long evolution times, t|h/c|, where t30 ms in a sodium Bose-Einstein condensate and c is the spin-exchange collisional energy. They give rise to quantum phase transitions that can generate massive entanglement. The ground state depends uniquely on whether the gas is antiferromagnetic (c0, Na), where it is massively entangled, or ferromagnetic (c0, Rb), where it is not entangled. The goal of this project is to make use of the unique features of ultracold sodium, and recent technological advances in matter-wave quantum optics, to demonstrate a robust and future-proof platform for matter-wave quantum technologies that will lay the groundwork for extensive long-term research on matter-wave devices similar to photonic devices. This is done by studying the following quantum technologies: a) quantum-enhanced sensing via spin-mixing interferometry in the long evolution time limit, b) quantum-enhanced probing of spin populations, c) quantum state synthesis of exotic many body states, and d) quantum simulation of the effect of impurities.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.

该项目由原子、分子和光学物理实验计划以及刺激竞争研究的既定计划（EPSCoR）共同资助。气体中原子之间的碰撞发生在我们周围，例如我们每天呼吸的空气中。在室温下，碰撞是随机的，很难控制。通过将气体冷却到接近绝对零度（低于零下273摄氏度）的超冷温度，并将其捕获在真空室的中心，可以控制碰撞并用于开发新技术，如杂质的量子限制传感器。超冷气体的行为就像一个单一的量子力学对象，一个物质波。碰撞仍然发生在物质波中，但它们现在以可预测的方式发生。在钠物质波中，碰撞可以通过微波辐射精确控制。碰撞原子的行为就像小磁铁一样，其磁北极和南极由原子自旋的方向决定。在碰撞过程中，原子会经历彼此的磁场并改变它们的自旋方向。当它们改变方向时，原子自旋在量子水平上相互关联，这种现象称为量子纠缠。当原子被用作传感器时，量子纠缠是有用的。所有纠缠的原子对外部影响的反应一致，增加了传感器的灵敏度。该研究项目将使用钠物质波中的受控碰撞来研究量子增强传感和其他量子技术。 该项目将研究杂质的作用，并探索与纠缠光束实验相比的差异和相似之处。这项研究将提高我们对基于物质波的量子技术的实验理解，在现实条件下，在存在损失和杂质的情况下。这对于开发强大的量子增强传感器，开发超冷气体的量子增强探针，以及提高我们对如何在量子水平上控制物质波自旋的理解具有实际应用。该研究计划的目标是研究基于物质波量子工程的新一代量子技术，例如用于具有高空间分辨率的外部场的量子增强传感器，用于测量具有降低的噪声的自旋布居的超冷原子样品的量子增强探针，以及量子增强物质波装置例如相敏放大器，类似于从光的量子光学已知的那些。在长演化时间的限制下，钠原子玻色-爱因斯坦凝聚体中物质波的控制是通过微波修饰和射频控制自旋交换碰撞来实现的。在F=1钠气体中的自旋交换碰撞过程中，磁量子数m=0的原子对碰撞并变成m=+/-1的原子对，反之亦然。这个过程产生了类似于光的四波混频的量子纠缠。但是，由于哈密顿量中的额外项在光子系统中不存在，因此原子系统中存在重要的差异。这些差异在漫长的进化过程中变得越来越重要，|H/C|其中，钠玻色-爱因斯坦凝聚中的t30 ms，c是自旋交换碰撞能量。它们引起量子相变，可以产生大量的纠缠。基态唯一地取决于气体是反铁磁的（c 0，Na），在那里它是大量纠缠的，还是铁磁的（c 0，Rb），在那里它不是纠缠的。该项目的目标是利用超冷钠的独特功能以及物质波量子光学的最新技术进展，为物质波量子技术展示一个强大且面向未来的平台，这将为广泛的长期研究奠定基础。这是通过研究以下量子技术来实现的：a）在长演化时间限制中通过自旋混合干涉测量的量子增强感测，B）自旋布居的量子增强探测，c）奇异多体态的量子态合成，（d）该奖项反映了NSF的法定使命，并通过使用基金会的知识产权进行评估，被认为值得支持。优点和更广泛的影响审查标准。

项目成果

A versatile microwave source for cold atom experiments controlled by a field programmable gate array

由现场可编程门阵列控制的用于冷原子实验的多功能微波源

• DOI: 10.1063/1.5127880
• 发表时间: 2020
• 期刊: Review of Scientific Instruments
• 影响因子: 1.6
• 作者: Morgenstern, Isaiah;Zhong, Shan;Zhang, Qimin;Baker, Logan;Norris, Jeremy;Tran, Bao;Schwettmann, Arne
• 通讯作者: Schwettmann, Arne

Seeded spin-mixing interferometry with long-time evolution in microwave-dressed sodium spinor Bose-Einstein condensates

微波处理钠自旋玻色-爱因斯坦凝聚体中种子自旋混合干涉测量的长期演化

• DOI: 10.1088/1361-6455/acc36f
• 发表时间: 2023
• 期刊: Molecular and Optical Physics
• 作者: Zhong, Shan;Ooi, Hio Giap;Prajapati, Sankalp;Zhang, Qimin;Schwettmann, Arne
• 通讯作者: Schwettmann, Arne

Quantum interferometry with microwave-dressed F=1 spinor Bose-Einstein condensates: Role of initial states and long-time evolution

• DOI: 10.1103/physreva.100.063637
• 发表时间: 2017-06
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: Qimin Zhang;A. Schwettmann

Dynamical mean-field-driven spinor-condensate physics beyond the single-mode approximation

• DOI: 10.1103/physreva.107.053309
• 发表时间: 2023-01
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: J. Jie;S. zhong;Q. Zhang;I. Morgenstern;H. G. Ooi;Q. Guan;A. Bhagat;D. Nematollahi;A. Schwettmann;D. Blume

Mean-field spin-oscillation dynamics beyond the single-mode approximation for a harmonically trapped spin-1 Bose-Einstein condensate

• DOI: 10.1103/physreva.102.023324
• 发表时间: 2020-08
• 期刊: Physical Review A
• 影响因子: 2.9
• 作者: J. Jie;Q. Guan;S. Zhong;A. Schwettmann;D. Blume