CAREER: Non-Equilibrium Coherent Many-Body Dynamics with Cold Atoms

职业：冷原子的非平衡相干多体动力学

• 批准号: 1148957
• 负责人: Andrew Daley
• 金额: $ 47.48万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1148957&HistoricalAwards=false
• 关键词: CAREER; Non; Equilibrium; Coherent; Many

In this project, non-equilibrium dynamics in systems of cold atoms and molecules is being explored, as motivated by the unique properties of those systems. The goals are (i) to obtain a better understanding of non-equilibrium dynamics in strongly interacting systems, and (ii) to use non-equilibrium dynamics as a benchmark for characterizing where quantum simulators can be used to explore physics beyond what is possible with classical simulations. In the first part of the project we are studying (a) paradigms of transport dynamics, including the engineering and measurement of currents by coupling the system to a reservoir gas or a cavity mode, as well as purely coherent propagation of excitations engineered in the system; and (b) dynamics in the presence of dipolar interactions, as motivated by recent experimental developments with polar molecules, including the time-dependence of phase transition processes and thermalization of excitations. In each case, the dynamics are bein explored using a combination of analytical techniques and numerical methods, including time-dependent Density Matrix Renormalisation Group methods for 1D systems. Extensions of these methods to the treatment of dynamics with long range interactions will also be investigated. In the second part of the project, we explore possibilities to measure entanglement entropies in experiments, and use these measurements to gain a deeper understanding of many-body dynamics in these systems.Understanding the non-equilibrium dynamics of microscopic many-particle systems is crucial to the description of very fundamental phenomena occurring in nature, including how a gas of particles reaches thermal equilibrium, and how moving conduction electrons in solids behave in quantum transport processes. Recent developments in experiments with ultracold gases of atoms and molecules have made it possible to explore such non-equilibrium dynamics in highly controllable systems, which can be manipulated and measured by well-understood processes in laser fields. In the research part of this project, we investigate how the unique properties of these systems, which are now available in the laboratory can be used to gain insight into fundamental aspects of non-equilibrium dynamics, including transport processes and thermalization. We will look to gain a deeper understanding of these process through our calculations, and to set a roadmap for the exploration of these phenomena in potential future experiments. We will also investigate means to measure the quantum mechanical entanglement in these experiments, which could be used both to gain further insight into the dynamics, and to demonstrate regimes where a quantum mechanical experiment realizes dynamics that go beyond what is computable with state-of-the-art numerical methods. The broader impacts of the supported work will also be enhanced by the education part of this project, where we will run a series of workshops in which basic concepts in quantum mechanics are explained to high-school teachers based on illustrative examples from current technologies, as well as from the research in this project. With the teachers we will explore possibilities and develop tools to communicate basic concepts in modern physics research to high school students.

在这个项目中，由于这些系统的独特性质，正在探索冷原子和分子系统中的非平衡动力学。目标是（i）更好地理解强相互作用系统中的非平衡动力学，以及（ii）使用非平衡动力学作为表征量子模拟器可用于探索超出现有物理范围的物理的基准。经典模拟。在该项目的第一部分中，我们正在研究（a）输运动力学范例，包括通过将系统耦合到储层气体或腔模式来设计和测量电流，以及系统中设计的激励的纯相干传播; (b) 偶极相互作用下的动力学，由最近极性分子实验发展的推动，包括相变过程的时间依赖性和激发的热化。在每种情况下，都使用分析技术和数值方法的组合来探索动力学，包括一维系统的时间相关密度矩阵重整化群方法。还将研究这些方法扩展到处理长程相互作用的动力学。在该项目的第二部分中，我们探索在实验中测量纠缠熵的可能性，并利用这些测量来更深入地了解这些系统中的多体动力学。了解微观多粒子系统的非平衡动力学至关重要描述自然界中发生的非常基本的现象，包括粒子气体如何达到热平衡，以及固体中移动的传导电子在量子传输过程中如何表现。原子和分子超冷气体实验的最新进展使得在高度可控的系统中探索这种非平衡动力学成为可能，这些系统可以通过激光领域中众所周知的过程来操纵和测量。在该项目的研究部分，我们研究了如何利用这些系统的独特性质（现已在实验室中使用）来深入了解非平衡动力学的基本方面，包括传输过程和热化。我们将通过计算来更深入地了解这些过程，并为在未来潜在的实验中探索这些现象制定路线图。我们还将研究测量这些实验中量子力学纠缠的方法，这既可以用来进一步了解动力学，也可以用来演示量子力学实验实现超越状态可计算动力学的机制。最先进的数值方法。该项目的教育部分也将增强所支持工作的更广泛影响，我们将举办一系列研讨会，根据当前技术的说明性示例向高中教师解释量子力学的基本概念，例如以及该项目的研究。我们将与老师一起探索可能性并开发工具，向高中生传达现代物理研究的基本概念。