CAREER: Topology and symmetry in non-equilibrium quantum systems

职业：非平衡量子系统的拓扑和对称性

基本信息

批准号：
1752759
负责人：
Anushya Chandran
金额：
$ 57.5万
依托单位：
Trustees of Boston 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：
2018-05-01 至 2024-04-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1752759&HistoricalAwards=false
关键词：
CAREER Topology symmetry non equilibrium

项目摘要

NONTECHNICAL SUMMARYThis CAREER award supports theoretical research and education in the dynamics of complex quantum systems away from equilibrium. Recent experimental advances in laser physics have enabled the control of electrons in materials at ultrafast time scales, before they can equilibrate. Likewise, the production of ultracold gases of atoms that are well isolated from their surroundings has enabled the real-time observation of their quantum dynamics. These developments have opened up a new regime of inquiry within quantum mechanics. This research seeks to elucidate complex quantum dynamics in specific settings.The most unexpected discovery in this context is that even extremely energetic quantum particles can remain spatially localized under a broad range of experimental conditions. This is in striking contrast with usual intuition from classical mechanics: if one rapidly shakes a box full of marbles, they do not stay still. When quantum particles localize, not only do they stay still, but they also become potentially usable for controlled quantum computation. The project aims to clarify the precise conditions under which this localization arises, determine near-term experimental observables, and build towards a complete theory of this poorly understood phenomenon. On driving the support of a simple pendulum quickly, the effects of gravity can be undone: the pendulum bob can settle in the inverted position above the point of support. Recent experiments in electronic systems suggest that strong laser radiation can similarly stabilize exotic quantum effects, such as superconductivity at short times, in materials which do not normally superconduct. Another aim of the project is to develop a theory of such dynamically stabilized states so as to control and engineer them for computation and other applications.In addition to mentoring and training graduate and undergraduate students participating in the research program, the PI aims to inspire local middle- and high-school students to explore careers in STEM through "Physics days" involving lab tours, demonstrations, and faculty interactions. Furthermore, this award will support the PI's role in a new public lecture series, which aims to engage the broader Boston community on everyday physics and the frontiers of research. As the future of nonequilibrium physics increasingly relies on physicists with interdisciplinary skills, the PI proposes to develop a new course unifying the approaches to out-of-equilibrium physics in quantum, optical, and biological settings. TECHNICAL SUMMARYThis CAREER award supports theoretical research and education in discovering, characterizing, and controlling quantum orders in many-body systems far from equilibrium. Through a multipronged approach that includes studies in model systems, developing general theorems about quantum steady states, perturbation theory and numerical computation, this project proposes to address the following fundamental issues:1) Strong quenched disorder can indefinitely prevent local equilibration in a well-isolated system, a remarkable phenomenon known as many-body localization. The PI will investigate foundational aspects of many-body localization in higher dimensions, in quasiperiodic settings, and the interplay of localization and topology.2) Exotic nonequilibrium orders with no equilibrium counterpart can arise in driven quantum systems, offering a unique window into robust quantum coherent many-body phenomena. The PI will discover and classify the complex orders accessible with multitone driving and investigate their stability.3) Environmental properties are crucial in state preparation and stabilizing fragile topological states. The PI will investigate the properties of unconventional environments, including anyon baths and baths with memory in experimentally relevant systems and extract their universal features.Remarkable experimental advances in the past decade in the ultrafast spectroscopy of correlated materials and in the construction of well-isolated ultracold atomic and molecular gases have brought real-time dynamics of many-body quantum systems into sharp focus. Concurrently, the quest to build a quantum computer in experimental platforms like superconducting qubits and trapped ions has raised many interesting questions about coherence in driven dissipative systems and has led to a rich exchange of ideas between quantum information theory and condensed matter. Theoretically, the understanding of far-from-equilibrium systems remains challenging because the assumptions underlying statistical mechanics typically fail to apply. The proposed research seeks to broadly advance our understanding of quantum many-body dynamics in closed, driven, and open settings, and to specifically apply it to the observation of novel quantum orders in dynamical settings. The development of new computational methods and the understanding of microscopic time scales in realistic experimental systems will also be a priority.In addition to mentoring and training graduate and undergraduate students participating in the research program, the PI aims to inspire local middle- and high-school students to explore careers in STEM through "Physics days" involving lab tours, demonstrations, and faculty interactions. Furthermore, this award will support the PI's role in a new public lecture series, which aims to engage the broader Boston community on everyday physics and the frontiers of research. As the future of nonequilibrium physics increasingly relies on physicists with interdisciplinary skills, the PI proposes to develop a new course unifying the approaches to out-of-equilibrium physics in quantum, optical, and biological settings.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.

非技术摘要该职业奖支持远离平衡的复杂量子系统动力学的理论研究和教育。激光物理学的最新实验进展使得能够在材料达到平衡之前以超快的时间尺度控制材料中的电子。同样，与周围环境完全隔离的原子产生的超冷气体使得能够实时观察其量子动力学。这些发展开辟了量子力学研究的新领域。这项研究旨在阐明特定环境下复杂的量子动力学。在这种情况下最意想不到的发现是，即使是能量极高的量子粒子也可以在广泛的实验条件下保持空间局域化。这与经典力学的通常直觉形成鲜明对比：如果一个人快速摇动装满弹珠的盒子，它们就不会保持静止。当量子粒子局域化时，它们不仅保持静止，而且还可能用于受控量子计算。该项目旨在阐明这种局域化发生的精确条件，确定近期的实验观测结果，并为这种人们知之甚少的现象建立一个完整的理论。在快速驱动简单摆的支撑时，重力的影响可以被消除：摆锤可以稳定在支撑点上方的倒置位置。最近的电子系统实验表明，强激光辐射同样可以稳定奇异的量子效应，例如通常不超导的材料中短时间的超导性。该项目的另一个目标是开发这种动态稳定状态的理论，以便控制和设计它们以进行计算和其他应用。除了指导和培训参与研究项目的研究生和本科生外，PI 还旨在激励当地中学生和高中生通过“物理日”探索 STEM 职业，其中包括实验室参观、演示和教师互动。此外，该奖项将支持 PI 在新的公开讲座系列中的作用，该系列讲座旨在让更广泛的波士顿社区参与日常物理学和研究前沿。随着非平衡物理学的未来越来越依赖于具有跨学科技能的物理学家，PI 建议开发一门新课程，统一量子、光学和生物环境中非平衡物理学的方法。技术摘要该职业奖支持在远离平衡的多体系统中发现、表征和控制量子序的理论研究和教育。通过多管齐下的方法，包括模型系统的研究、发展有关量子稳态的一般定理、微扰理论和数值计算，该项目建议解决以下基本问题：1）强淬灭无序可以无限期地阻止良好隔离的局部平衡系统，这是一种被称为多体定位的显着现象。 PI 将研究更高维度、准周期设置中多体局域化的基本方面，以及局域化和拓扑的相互作用。2) 驱动量子系统中可能会出现没有平衡对应物的奇异非平衡阶，从而为了解鲁棒量子提供了一个独特的窗口连贯的多体现象。 PI 将发现并分类可通过多音驱动访问的复杂阶，并研究其稳定性。3) 环境属性对于状态准备和稳定脆弱的拓扑状态至关重要。 PI将研究非常规环境的特性，包括实验相关系统中的任意子浴和记忆浴，并提取它们的普遍特征。过去十年在相关材料的超快光谱和良好隔离的超冷构造方面取得了显着的实验进展原子和分子气体使多体量子系统的实时动力学成为人们关注的焦点。与此同时，在超导量子位和俘获离子等实验平台中构建量子计算机的探索提出了许多关于驱动耗散系统的相干性的有趣问题，并导致了量子信息理论和凝聚态物质之间丰富的思想交流。从理论上讲，对远离平衡系统的理解仍然具有挑战性，因为统计力学的假设通常无法适用。拟议的研究旨在广泛推进我们对封闭、驱动和开放环境中的量子多体动力学的理解，并将其专门应用于动力学环境中新量子序的观察。新计算方法的开发以及对现实实验系统中微观时间尺度的理解也将是一个优先事项。除了指导和培训参与研究项目的研究生和本科生外，PI还旨在激励当地的中高中生学校学生通过“物理日”探索 STEM 职业，其中包括实验室参观、演示和教师互动。此外，该奖项将支持 PI 在新的公开讲座系列中的作用，该系列讲座旨在让更广泛的波士顿社区参与日常物理学和研究前沿。由于非平衡物理学的未来越来越依赖于具有跨学科技能的物理学家，PI 建议开发一门新课程，统一量子、光学和生物环境中非平衡物理学的方法。该奖项反映了 NSF 的法定使命，并已被通过使用基金会的智力优点和更广泛的影响审查标准进行评估，认为值得支持。