Exploring New Frontiers in Spin-1 Dynamics, Geometry and Metrology

这项研究将探索冷却到接近绝对零度的小原子云的行为，并主要通过它们的磁自旋相互作用。这项研究将促进对多粒子系统量子动力学的基本理解，这是一个对凝聚态物理、核物理和天体物理很重要的基础物理领域。此外，这项研究还将为重要的技术应用提供信息，包括用于导航和磁力测量的精密传感器、原子钟以及包括量子信息和通信在内的新兴量子技术。实验使用的是由Rb-87原子组成的小云，这些原子被冷却到绝对零度以上不到100纳开尔文的温度，并在真空房间中被激光限制。在这些低温下，原子形成玻色-爱因斯坦凝聚体，这是物质的一种独特的量子相。这个项目主要关注原子的本征自旋的动力学，这是量子磁学的一个基本组成部分。这些实验的特点是使用外场精确控制原子的量子态，良好描述的动力学，量子相变，以及低噪声层析量子态测量能力。这些工具将允许研究临界点附近量子相变的有限尺寸效应，演示创建和控制系综高度纠缠态的新方法，以及研究自旋1系统独有的新的非阿贝尔几何相位。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 research will explore the behavior of small clouds of atoms cooled close to absolute zero and interacting primarily via their magnetic spins. This research will advance the fundamental understanding of the quantum dynamics of many-particle systems, which is an area of fundamental physics important to condensed matter physics, nuclear physics and astrophysics. In addition, this research will inform important technological applications including precision sensors for navigation and magnetometry, atomic clocks and emerging quantum technologies including quantum information and communication.The experiments use small clouds of rubidium-87 atoms that are cooled to temperatures less than 100 nanoKelvin above absolute zero and confined with laser beams in an evacuated chamber. At these low temperatures, the atoms form a Bose-Einstein condensate, which is a unique quantum phase of matter. This project focuses on the dynamics of the intrinsic spin of the atoms, which is a fundamental component of quantum magnetism. The experiments feature precise control of the quantum states of the atoms using external fields, a well-characterized dynamics, a quantum phase transition, and low-noise tomographic quantum state measurement capabilities. These tools will permit studies of finite size effects of a quantum phase transition in the neighborhood of the critical point, demonstration of new methods of creating and controlling highly entangled states of the ensembles, and investigation of new non-Abelian geometrical phases unique to spin-1 systems.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.