Interacting Atoms in Optical Lattices

光学晶格中相互作用的原子

基本信息

批准号：
2012039
负责人：
David Weiss
金额：
$ 68.37万
依托单位：
Pennsylvania State Univ University Park
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012039&HistoricalAwards=false
关键词：
Interacting Atoms Optical Lattices

项目摘要

General audience abstract:The frontier of the technological application of quantum mechanics involves taking advantage of quantum entanglement, where the detailed interactions among particles are of central importance. Such emerging technologies include quantum simulators, quantum computers and quantum communication, as well as advanced versions of older quantum technologies like quantum sensors and clocks. Advancing these technologies requires understanding the dynamics of closed ‘quantum many-body systems,’ i.e. systems containing many particles which interact with each other and where quantum mechanics is important. The goal of this work is to help develop a universal description of such dynamics. The researchers will experimentally study the quantum many-body system that currently has the most complete equilibrium theoretical description, one-dimensional gases, which they make by putting ultracold atoms into optical lattices (periodic structures made from laser light). By taking these gases out of equilibrium, in situations where entanglement dominates dynamics, they can cleanly test emerging theoretical approaches. The experimental system can be made progressively more complex, so that the theories used to describe them can encompass a wide range of non-equilibrium systems. The largest immediate impact is likely to be in our understanding of the reliability of quantum simulators and the robustness of quantum computers. The training in experimental physics obtained by undergraduates and graduate students working on this experiment is comprehensive and is good preparation for many different types of experimental work.Technical audience abstract:The PI and his students will perform a series of measurements on one-dimensional (1D) Bose gases, which consist of ultra-cold 87Rb atoms trapped in a 2D array of tubes that are made with a 2D optical lattice. These interacting many-body systems are integrable, which implies that they are characterized by a large set of extra conserved quantities. The experiments generally involve taking these systems out of equilibrium and studying the ensuing dynamics. Unlike generic many-body quantum systems, the equilibrium properties of 1D gases can be calculated exactly. Their non-equilibrium properties, however, have been a challenge to calculate. A recently developed numerical technique, generalized hydrodynamics (GHD), promises to describe, to within certain approximations, the dynamics of integrable systems. GHD is based upon keeping track of the evolving local distribution of ‘rapidities’, which are the momenta associated with the quasiparticles that emerge in integrable systems. These important but abstract objects have only recently been measured (by the PI’s team) and the team plans to measure them in a much more diverse set of circumstances. With these measurements will come the ability to quantitatively test GHD for the first time in the interesting intermediate and strong coupling regimes. They will also study the border at which GHD becomes applicable, by measuring the evolution of momentum and rapidity distributions after a wavefunction quench. Finally, they propose to extend these studies to a 1D gas in a weak lattice, a non-integrable system for which GHD might also be a useful description, at least at relatively short times. The search for a universal description of dynamics in quantum many-body systems is an important physics frontier, and GHD holds the promise of providing its core.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.

普通受众摘要：量子力学技术应用的前沿涉及利用量子纠缠，其中粒子之间的详细相互作用至关重要。这样的新兴技术包括量子模拟器，量子计算机和量子通信，以及旧量子技术（如量子传感器和时钟）的先进版本。推进这些技术需要了解封闭的“量子多体系统”的动力学，即包含许多彼此相互作用以及量子力学很重要的系统。这项工作的目的是帮助开发对这种动态的普遍描述。研究人员将在实验上研究当前具有最完整的平等理论描述，一维气体的量子多体系统，它们通过将超电原子放入光学晶格（周期性结构）中制成的一维气体。通过将这些气体从平衡中取出，在纠缠占主导地位的情况下，它们可以清洁测试出现的理论方法。实验系统可以逐渐变得更加复杂，因此用来描述它们的理论可以包含广泛的非平衡系统。最大的直接影响可能是我们对量子模拟器的可靠性和量子计算机的鲁棒性的理解。 The training In experimental physics obtained by undergraduates and graduate students working on this experiment is comprehensive and is good preparation for many different types of experimental work.Technical audience abstract:The PI and his students will perform a series of measurements on one-dimensional (1D) Bose gases, which consist of ultra-cold 87Rb atoms trapped in a 2D array of tubes that are made with a 2D optical lattice.这些相互作用的多体系统是可以集成的，这意味着它们的特征是大量额外的保守量。实验通常涉及将这些系统摆脱平衡并研究确保动态。与通用多体量子系统不同，可以精确计算一维气体的平衡性能。但是，它们的非平衡性能是计算的挑战。一种最近开发的数值技术，广义流体动力学（GHD），有望在某些近似值内描述可集成系统的动力学。 GHD基于跟踪“速度”的局部分布，这是与可集成系统中出现的准粒子相关的矩。这些重要但抽象的对象最近才被PI团队（PI团队）衡量，并且该团队计划在更多潜水员的情况下进行衡量。通过这些测量值，将能够在有趣的中间和强耦合方案中首次定量测试GHD。他们还将通过测量波力淬火后的动量和速度分布的演变来研究GHD适用的边界。最后，他们建议将这些研究扩展到弱晶格中的一维气体，这是一种不可融合的系统，至少在相对较短的时间，GHD也可能是有用的描述。搜索量子多体系统动态的普遍描述是重要的物理领域，而GHD则具有提供其核心的希望。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响来评估NSF的法定任务。