CAREER: New Regimes of Coherent Nonequilibrium Dynamics in Quantum Many-Body Systems

非技术总结这个职业奖支持理论研究和教育在非平衡量子动力学的广泛领域，以期对新兴的量子技术。量子计算是一种新的计算模式，它利用量子力学的原理来存储和处理信息。快速的实验进展正在迎来一个有用的近期量子计算平台的时代，其潜在应用范围从密码学到药物设计。量子计算依赖于控制许多相互作用的量子粒子系统的非平衡动力学。因此，理解这种动态在推动未来进步方面发挥着关键作用。多粒子量子系统往往会丢失关于它们准备时状态的信息。这种被称为量子遍历性的趋势对量子计算是有害的，因为量子计算依赖于保持微妙的量子态并对其进行操作的能力。该项目的研究部分将发展对各种机制的理论理解，通过这些机制可以避免量子遍历性。该研究所还将考虑如何在当今的量子硬件上实现这些机制，其长期目标是扩大复杂量子系统研究和操纵的工具包。量子科学和技术已被确定为国家重点研究项目。要保持在这一领域的领导地位，需要培养一支强大的量子团队。为此，该项目的教育部分包括在爱荷华州州立大学（ISU）开发跨学科的量子计算课程，其成功将增加量子人才管道。首席研究员还将与国际空间大学领导的两项倡议“科学束缚”和“更进一步”合作，围绕量子物理主题开展外联活动，旨在增加科学，技术，工程和数学领域代表性不足的群体的参与。这些活动将接触到数百名预科生和大学生，并通过动手活动和主动学习方法，挖掘量子物理的流行兴奋点。技术总结该职业奖支持非平衡量子动力学广泛领域的理论研究和教育，以期发展新兴的量子技术。研究部分解决了量子多体系统如何在强相互作用的存在下无法放松到热平衡并保持量子相干性的基本问题。研究活动分为三个相互关联的方向，其目标是：（1）阐明涌现动力学约束在规范理论和相关量子自旋模型的远离平衡行为中的作用。这个问题将使用微扰理论和数值精确对角化相结合的研究，以提取在这样的系统中的弛豫过程的时间尺度。(2)探索量子多体伤疤的一般构造，这是一种动力学机制，通过在一类特殊的初始状态下准备系统，可以避免热化。该结构依赖于无限温度热场双态的使用，这在高能物理和量子信息科学界都很感兴趣。(3)发现量子电路固有的热化和退相干的新障碍，量子计算的自然环境。该项目的重点是与经典细胞自动机相关的量子电路，以及基于确定性非周期序列的电路。所有这三个主题都与当今的实验平台有关，包括玻色子和费米子的冷原子气体，光镊中的里德伯原子阵列，以及当今嘈杂的中等规模量子硬件。该项目的教育部分包括在爱荷华州州立大学（ISU）开发跨学科的量子计算课程，其成功将增加量子人才管道。PI还将与国际空间大学领导的两项倡议“科学界限”和“更进一步”合作，围绕量子物理主题开展外联活动，旨在增加科学，技术，工程和数学领域代表性不足的群体的参与。这些活动将接触到数百名预科生和大学生，并通过实践活动和主动学习方法，激发人们对量子物理的热情。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

NONTECHNICAL SUMMARYThis CAREER award supports theoretical research and education in the broad field of nonequilibrium quantum dynamics with a view towards emerging quantum technologies. Quantum computing is a new mode of computation that harnesses the principles of quantum mechanics to store and process information. Rapid experimental progress is ushering in an era of useful near-term quantum computing platforms, with potential applications ranging from cryptography to drug design. Quantum computation relies on controlling the nonequilibrium dynamics of systems of many interacting quantum particles. Comprehending such dynamics thus plays a critical role in enabling future advances. Many-particle quantum systems tend to lose information about the state in which they were prepared. This tendency, known as quantum ergodicity, is detrimental to quantum computation, which hinges on the ability to preserve delicate quantum states and perform operations on them. The research component of this project will develop a theoretical understanding of a variety of mechanisms through which quantum ergodicity can be avoided. It will also consider how to realize these mechanisms on present-day quantum hardware with the long-term goal of expanding the toolkit for the study and manipulation of complex quantum systems.Quantum science and technology has been identified as a key national research priority. Sustaining leadership in this field requires nurturing a robust quantum workforce. To this end, the education component of this project includes developing an interdisciplinary quantum computing curriculum at Iowa State University (ISU), whose success will grow the quantum talent pipeline. The principal investigator will also engage in outreach around quantum physics topics in partnership with two ISU-led initiatives, Science Bound and Go Further, aimed at increasing the participation of underrepresented groups in science, technology, engineering, and mathematics. These activities will reach hundreds of precollege and college students and tap into popular excitement about quantum physics using hands-on activities and active learning approaches.TECHNICAL SUMMARYThis CAREER award supports theoretical research and education in the broad field of nonequilibrium quantum dynamics with a view towards emerging quantum technologies. The research component addresses the foundational question of how quantum many-body systems can fail to relax to thermal equilibrium and maintain quantum coherence in the presence of strong interactions. Research activities are organized into three interrelated thrusts whose goals are: (1) Elucidate the role of emergent dynamical constraints in the far-from-equilibrium behavior of gauge theories and related quantum spin models. This question will be investigated using a combination of perturbation theory and numerical exact diagonalization to extract the timescales of relaxation processes in such systems. (2) Explore a general construction of quantum many-body scars, a dynamical regime where thermalization can be avoided by preparing the system in a special class of initial states. The construction hinges on the use of infinite-temperature thermofield-double states, which are of interest in both the high-energy physics and quantum information science communities. (3) Discover novel roadblocks to thermalization and decoherence intrinsic to quantum circuits, the natural setting for quantum computation. This project focuses on quantum circuits related to classical cellular automata, as well as circuits based on deterministic aperioidic sequences. All three topics are relevant to present-day experiments on platforms including cold atomic gases of bosons and fermions, arrays of Rydberg atoms in optical tweezers, and present day noisy intermediate-scale quantum hardware.The education component of this project includes developing an interdisciplinary quantum computing curriculum at Iowa State University (ISU), whose success will grow the quantum talent pipeline. The PI will also engage in outreach around quantum physics topics in partnership with two ISU-led initiatives, Science Bound and Go Further, aimed at increasing the participation of underrepresented groups in science, technology, engineering, and mathematics. These activities will reach hundreds of precollege and college students and tap into popular excitement about quantum physics using hands-on activities and active learning approaches.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.