Strongly Correlated Quantum Systems: From Electronic Materials to Cold Atoms to Photons

强相关的量子系统：从电子材料到冷原子再到光子

• 批准号: 0705472
• 负责人: Eugene Demler
• 金额: $ 39万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0705472&HistoricalAwards=false
• 关键词: Strongly; Correlated; Quantum; Systems; Electronic

TECHNICAL SUMMARY:This award supports theoretical research and education at the interface of theoretical condensed matter physics and atomic physics. Advances in physics come from mutual stimulation of theory and experiments. In the field of ultracold atoms theoretical ideas about Feshbach resonances, optical lattices, and low dimensional systems lead to experimental realization of several types of strongly correlated many body systems. Future progress in the field requires theoretical input into developing new methods for creation, manipulation, identification, and characterization of novel quantum states of matter realized with cold atoms. One of the goals of this research is to develop new theoretical tools for studying coherent dynamics of strongly correlated quantum systems. Understanding non-equilibrium dynamics of interacting many-body systems is crucial for making contact with experiments on ensembles of cold atoms. Theoretical techniques will include perturbative expansions, analysis of effective field theories, application of exact solutions, numerical methods for lattice systems. This project will adopt a strategy of considering particular systems with a goal of developing general tools for studying dynamics of interacting fermionic and bosonic systems and bringing out a common framework for understanding the physics of strongly correlated states of matter. Another goal of this project is to find new ways of characterizing non-trivial correlations of interacting many body systems using experimental techniques appropriate for cold atoms ensembles. Novel approaches to examining the data, such as quantum noise analysis of the time of flight experiments and analysis of fringe visibility in interference experiments will be emphasized. The theoretical investigation of new methods for creating strongly correlated systems is also an essential part of this project. This project will explore a variety of possibilities starting from non mean field states of spinor condensates and polar molecules in optical lattices to a Tonks gas of photons in a hollow optical fiber. The idea of the latter is to create a one dimensional system of photons where optical non-linearity is so large that photons become essentially impenetrable particles. Such a system should exhibit features of photon "fermionization" including the appearance of strong photon antibunching and crystal like correlations. It should provide a new intriguing interface between nonlinear quantum optics and strongly correlated electron systems. Another component of this project involves exploring new methods for studying strongly correlated states of electrons in solids using recent progress in a variety of experimental techniques, including resonant soft x-ray scattering, double photoemission spectroscopy, and high resolution scanning tunneling microscopy.Training students and postdoctoral researchers is a vital component of this project. Students and postdocs are actively involved in the research of the PI and are exposed to a wide range of problems in several areas of physics. NON-TECHNICAL SUMMARY:This award supports theoretical research and education at the interface of theoretical condensed matter physics and atomic physics. This research project focuses on new states of matter that arise in systems of atoms trapped by light, and in low-energy electrons in complex materials. In these systems and materials, the atoms or the electrons interact strongly with each other resulting in the emergence of new states of matter with intriguing properties that often display fundamentally new phenomena. Advanced tools of theoretical research will be brought to bear to understand possible new states of matter and propose new ways to experimentally probe these systems and to manipulate their quantum mechanical states so as to identify new states of matter and discover their subtle nature. The study of cold atoms trapped in periodic lattices of light offer the possibility to explore strongly interacting systems in ways that are not possible for electrons in materials. Advances in understanding one area enable advances in the other. The unusual properties of new states of matter however they are manifest and the unusual phenomena associated with them are of no less fundamental interest and importance than any other aspect of our universe. Understanding how to manipulate newly discovered quantum mechanical states of matter offers the possibility of powerful new ways to perform computation and new device technologies that will help keep America competitive. Training students and postdoctoral researchers is a vital component of this project. Students and postdocs are actively involved in the research and are exposed to a wide range of problems in several areas of physics. This project contributes to the high caliber scientifically trained workforce of the next generation.

技术综述：该奖项支持理论凝聚态物理和原子物理交界处的理论研究和教育。物理学的进步来自于理论和实验的相互促进。在超冷原子领域，关于Feshbach共振、光学晶格和低维系统的理论思想导致了几种类型的强关联多体系统的实验实现。未来该领域的进展需要理论投入，以开发新的方法来创建、操作、识别和表征用冷原子实现的物质的新量子态。这项研究的目标之一是发展新的理论工具来研究强关联量子系统的相干动力学。了解相互作用多体系统的非平衡动力学对于接触冷原子系综的实验是至关重要的。理论技术包括微扰展开、有效场论分析、精确解的应用、格子系统的数值方法。这个项目将采用一种考虑特定系统的策略，目的是开发通用工具来研究费米子和玻色子相互作用系统的动力学，并提出一个理解强关联物质态物理的共同框架。该项目的另一个目标是利用适用于冷原子系综的实验技术，找到表征相互作用的多体系统的非平凡关联的新方法。将强调检查数据的新方法，如飞行时间实验的量子噪声分析和干涉实验中的条纹可见度分析。创建强关联系统的新方法的理论研究也是该项目的重要组成部分。这个项目将探索各种可能性，从光学晶格中旋量凝聚体和极性分子的非平均场态开始，到中空光纤中的唐克斯光子气体。后者的想法是创建一个一维光子系统，其中光学非线性如此之大，以至于光子基本上成为不可穿透的粒子。这样的系统应该表现出光子“费米化”的特征，包括出现强光子反聚束和类晶体关联。它应该在非线性量子光学和强关联电子系统之间提供一个新的有趣的接口。该项目的另一个组成部分包括利用各种实验技术的最新进展来探索研究固体中强关联电子状态的新方法，包括共振软X射线散射、双光电发射光谱和高分辨率扫描隧道显微镜。培训学生和博士后研究人员是该项目的重要组成部分。学生和博士后积极参与PI的研究，并接触到多个物理领域的广泛问题。非技术综述：该奖项支持理论凝聚态物理和原子物理交界处的理论研究和教育。这项研究项目的重点是在被光捕获的原子系统中出现的新的物质状态，以及复杂材料中的低能电子。在这些系统和材料中，原子或电子相互作用强烈，导致新的物质状态的出现，这些新的物质状态具有有趣的性质，通常表现出根本上的新现象。先进的理论研究工具将被用来理解物质可能的新状态，并提出新的方法来从实验上探索这些系统，并操纵它们的量子力学状态，以识别新的物质状态，并发现它们的微妙性质。对被困在周期性光晶格中的冷原子的研究提供了以材料中电子不可能的方式探索强相互作用系统的可能性。对一个领域的理解的进步使另一个领域的进步成为可能。然而，新物质状态的不同寻常的性质是显而易见的，与之相关的不同寻常的现象与我们宇宙的任何其他方面一样具有根本的兴趣和重要性。了解如何操纵新发现的物质的量子力学状态，为实现强大的计算和新设备技术提供了可能性，这将有助于保持美国的竞争力。培训学生和博士后研究人员是该项目的重要组成部分。学生和博士后积极参与这项研究，并接触到多个物理领域的广泛问题。该项目为下一代高素质的科学培训劳动力做出了贡献。