Microscopy of Bosonic Fractional Quantum Hall States in Optical Lattices

光学晶格中玻色子分数量子霍尔态的显微镜观察

• 批准号: 1806604
• 负责人: Markus Greiner
• 金额: $ 54万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1806604&HistoricalAwards=false
• 关键词: Microscopy; Bosonic; Fractional; Quantum; Hall

Fractional quantum Hall states, discovered by Tsui, Stormer and Gossard in two-dimensional electron systems, represent new states of matter that contain a novel kind of order - topological order. Understanding the physical origin that gives rise to such a behavior will profoundly enhance our perspective on topological materials and is promising for future applications such as topological quantum computers. However, the microscopic physics and quantum properties such as entanglement cannot be probed directly in quantum Hall condensed matter materials. Therefore, this project will build a model system using ultracold atoms in optical lattices. The atoms behave fully quantum mechanically and can serve as a quantum simulator. A quantum gas microscope enables full microscopic control, and will enable this team to shed light on the microscopic origin of fractional quantum Hall physics, and to directly probe quantum entanglement, which is essential for the future use of topological materials in quantum information. This project will also train students in atomic physics and condensed matter physics, and will help prepare them to participate in the high-tech work force.Since its discovery as quantized Hall conductance at fractional Landau level filling, the quantum Hall effect has been subject to intense theoretical and experimental study. Yet the microscopic mechanisms giving rise to many associated phenomena are not well understood, for example the nature of the many-body ground state, excitation properties (in particular the depedence on defects) or the role of a lattice structure. Theoretical studies suggest the fractional quantum Hall (FQH) effect should exist both for bosonic and fermionic particle statistics and have shown that the complexity arises from the interplay of strong interactions among the particles and topological features. This project will realize a system exhibiting the FQH effect by creating a strong synthetic gauge field in a few-boson system on a two-dimensional optical lattice. With the manipulation and detection techniques of a quantum gas microscope with single site resolution, this team will be able to determine the many-body state of the system by analyzing the density distribution on the level of single atoms. Furthermore, this team will work towards characterizing the global entanglement associated with the topological order by measuring the entanglement entropy of the system with a Hong-Ou-Mandel-type interference experiment.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.

TSUI，Stormer和Gossard在二维电子系统中发现的分数量子厅状态，代表了包含一种新型秩序的物质状态 - 拓扑顺序。了解产生这种行为的物理血统将深刻地增强我们对拓扑材料的看法，并有望在未来的应用中（例如拓扑量子计算机）。但是，微观物理和量子特性（例如纠缠范围）不能直接在量子厅凝结物质材料中进行探测。因此，该项目将使用光学晶格中的Ultracold Atoms构建模型系统。原子在机械上表现完全量子，可以用作量子模拟器。量子气体显微镜可以完全显微镜控制，并使该团队能够阐明分数量子霍尔物理学的显微镜起源，并直接探测量子纠缠，这对于未来在量子信息中使用拓扑材料至关重要。 该项目还将培训学生的原子物理和凝结物理学，并将帮助他们准备参加高科技劳动力。因为它的发现是分数Landau级填充的量化Hall电导，因此量子Hall的效应已进行了强烈的理论和实验性研究。然而，尚不清楚引起许多相关现象的微观机制，例如多体基态的性质，激发特性（尤其是对缺陷的依赖）或晶格结构的作用。理论研究表明，对于骨气和费米子粒子统计，应存在分数量子霍尔（FQH）效应，并表明复杂性来自粒子和拓扑特征之间强相互作用的相互作用。该项目将通过在二维光学晶格上在几个玻璃体系统中创建一个强大的合成量规场来实现表现出FQH效应的系统。借助具有单个位点分辨率的量子气显微镜的操纵和检测技术，该团队将能够通过分析单个原子水平上的密度分布来确定系统的多体状态。此外，该团队将通过通过Hong-ou-Mandel型干扰实验来衡量系统的纠缠熵与拓扑顺序相关的全球纠缠。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和广泛的影响来评估Criteria的智力功能和广泛的CRITERIA，并被认为是值得通过评估的支持。

项目成果

Quantum critical behaviour at the many-body localization transition

• DOI: 10.1038/s41586-019-1527-2
• 发表时间: 2018-12
• 期刊: Nature
• 影响因子: 64.8
• 作者: M. Rispoli;A. Lukin;R. Schittko;Sooshin Kim;M. Tai;J. Léonard;M. Greiner