Generalized Elasticity, Fluctuations and Stability of Soft Condensed

软凝聚体的广义弹性、波动与稳定性

• 批准号: 1001240
• 负责人: Leo Radzihovsky
• 金额: $ 42万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-15 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1001240&HistoricalAwards=false
• 关键词: Generalized; Elasticity; Fluctuations; Stability; Soft

TECNNICAL SUMMARYThis award supports theoretical studies and corresponding educational activities in condensed matter physics. The focus is on ostensibly ordered states of matter, characterized by an exceptionally "soft" elasticity, and are consequently strongly and qualitatively affected by fluctuations and local heterogeneity.The PI will study a number of experimentally motivated examples of such states, realized in a variety of unusual contexts.The PI will explore various states of matter including: uniaxially periodically ordered superfluids, such as the Larkin-Ovchinnikov state of a species-imbalanced paired superconductor and a bosonic smectic supersolid, and helical ground states of frustrated centrosymmetric and chiral noncentrosymmetric magnets.The PI will formulate a low-energy sigma-model description of such states, and will use it to investigate their low-energy properties and related phase transitions. Some of the key ingredients that will be incorporated are required Goldstone mode nonlinearities, novel topological defects, and new states arising from their proliferation, quantum dynamics, coupling to fermionic degrees of freedom, and the effects of various external fields.Another focus of the research is a class of condensed matter systems that exhibit bulk ordered states subjected to a random surface pinning, a liquid crystal cell with a "dirty" glass substrate being a prominent example. The PI will develop models for such systems and extensively explore a number of fundamental and applied aspects, including: the stability of phases to surface pinning, statistics and length scales characterizing distortions, topological defects, and effects of finite cell thickness and external fields.The research is planned to address real experimental problems and pushing the frontiers of theoretical condensed matter physics, the research will contribute to synergism between otherwise disparate subfields. This award supports educational and outreach efforts including: curriculum development of condensed matter physics, developing sophomore Modern Physics courses, and mentoring teachers, high school, and undergraduate students.NONTECHNICAL SUMMARYThis award supports theoretical studies and corresponding educational activities to study various new states of matter that are linked by a common property. These states of matter are considered to be "soft" and particularly susceptible to fluctuations whether they are thermal fluctuations described by statistical physics or quantum fluctuations that arise as a consequence of Heisenberg's famous uncertainty principle. Examples include magnets and superfluids, a quantum state of matter that is characterized by fluid flow without loss. Superfluids arise in a number of contexts. Superfluids involving charged particles are called superconductors and encompass wide class of materials. These "superstates" can also be realized by gases of atoms cooled to nearly the absolute zero of temperature using laser beams. The PI will study a number of experimentally motivated examples of such states, realized in a variety of unusual contexts.Some soft states of matter are also sensitive to impurities. A liquid crystal display with a "dirty" glass substrate might be a prominent example. The random impurities on the glass substrate can disrupt how the molecules of the liquid crystal orient themselves. The PI will use advanced theoretical techniques to study such systems with the aim of advancing fundamental understanding of how nature works. This research is planned to address real experimental problems and to push the frontiers of theoretical condensed matter physics. The research will contribute to synergism between otherwise disparate subfields. It may also contribute to the foundations of new technologies as the manipulation of states of matter and materials may lead to new phenomena that can form the basis for future device technologies. This award also supports educational and outreach efforts including: curriculum development of condensed matter physics, developing sophomore Modern Physics courses, and mentoring teachers, high school, and undergraduate students.

该奖项支持凝聚态物理学的理论研究和相应的教育活动。重点是表面上有序的物质状态，其特征是异常“软”的弹性，因此强烈和定性地受到波动和局部异质性的影响。PI将研究一些实验动机的例子，这些状态在各种不寻常的情况下实现。PI将探索各种物质状态，包括：单轴周期性有序超流体，例如物种不平衡配对超导体和玻色子近晶超固体的Larkin-Ovchinnikov态，和螺旋基态的阻挫中心对称和手征非中心对称磁体。PI将制定一个低能量西格玛模型描述这样的状态，并将用它来研究它们的低能特性和相关的相变。一些关键的成分将被纳入所需的Goldstone模式非线性，新的拓扑缺陷，和新的国家所产生的增殖，量子动力学，耦合到费米子自由度，和各种外场的影响。另一个研究重点是一类凝聚态系统，表现出大量有序状态受到随机表面钉扎，具有“脏”玻璃基板的液晶单元是一个突出的例子。PI将为这些系统开发模型，并广泛探索一些基本和应用方面，包括：相位对表面钉扎的稳定性、表征畸变的统计和长度尺度、拓扑缺陷以及有限单元厚度和外场的影响。这项研究计划解决真实的实验问题，并推动理论凝聚态物理学的前沿，这项研究将有助于其他不同的子领域之间的协同作用。 该奖项支持教育和推广工作，包括：凝聚态物理的课程开发，开发大二的现代物理课程，指导教师，高中和本科生。非技术总结该奖项支持理论研究和相应的教育活动，以研究由共同属性联系在一起的各种新的物质状态。这些物质状态被认为是“软”的，并且特别容易受到波动的影响，无论它们是统计物理学描述的热波动还是海森堡着名的不确定性原理引起的量子波动。例子包括磁铁和超流体，一种物质的量子态，其特征是流体流动而没有损失。超流体出现在多种背景下。涉及带电粒子的超流体被称为超导体，并且包含广泛的材料类别。这些“超态”也可以通过使用激光束冷却到接近绝对零度的原子气体来实现。PI将研究一些在各种不寻常的环境中实现的这种状态的实验性例子。一些物质的软态也对杂质敏感。 带有“脏”玻璃基板的液晶显示器可能是一个突出的例子。玻璃基板上的随机杂质会破坏液晶分子的取向。PI将使用先进的理论技术来研究这些系统，目的是促进对大自然如何运作的基本理解。这项研究计划解决真实的实验问题，并推动理论凝聚态物理学的前沿。 这项研究将有助于其他不同子领域之间的协同作用。它还可能有助于新技术的基础，因为对物质和材料状态的操纵可能导致新的现象，这些现象可以形成未来设备技术的基础。该奖项还支持教育和推广工作，包括：凝聚态物理的课程开发，开发大二现代物理课程，指导教师，高中和本科生。