Transient and steady-state properties far from equilibrium

远离平衡的瞬态和稳态特性

• 批准号: 1205309
• 负责人: Michel Pleimling
• 金额: $ 30万
• 依托单位: Virginia Polytechnic Institute and State University
• 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: 2012-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1205309&HistoricalAwards=false
• 关键词: Transient; steady; state; properties; far

TECHNICAL SUMMARYThis award supports theoretical research and education on interacting many-particle systems far from equilibrium. The PI will combine advanced analytical and numerical techniques and explore novel aspects of transient and steady state properties far from equilibrium. Two main research thrusts will be pursued. The first thrust focuses on relaxation processes far from equilibrium. Aging phenomena in systems with logarithmic growth remain poorly understood, even though many important disordered systems are expected to display this type of slow growth in the long time limit. The PI seeks to gain new insights into aging through the study of paradigmatic models, amenable both to numerical and analytical methods. Motivated by recent experiments on aging in artificial antiferromagnets, the PI plans to extend the study of relaxation to layered Ising systems with increasing complexity. A better understanding of aging processes in these systems should help establishing artificial antiferromagnets as the new paradigm for the experimental study of non-equilibrium processes in non-disordered systems. The PI aims to build on recent work that showed the existence of a duality between aging phenomena and gravitational physics in order to further open the field of non-equilibrium physics to string theoretical techniques. The second thrust focuses on non-equilibrium phase transitions that take place in inhomogeneous systems where the effects of surfaces and boundaries cannot be neglected. The PI will study phase transitions in two different inhomogeneous systems with energy input at a surface or a boundary: (1) bounded systems with magnetic friction and (2) systems with conserved dynamics where different sectors are in contact with different heat baths. The observed results, ranging from novel surface phase transitions to the emergence of convection cells and temperature driven transitions between striped phases, warrant an in-depth study in order to fully understand phase transitions in systems with local energy input. Due in part to the ubiquity of non-equilibrium processes in nature, this research has potential to have impact across disciplinaryboundaries. This project is designed so that both undergraduate and graduate students can contribute in a substantial and meaningful way, using a large variety of methods. This training through research approach allows students to be involved at every level in cutting-edge research projects.NONTECHNICAL SUMMARYThis award supports theoretical research and education on phenomena that occur in systems of many interacting particles far from the steady state of equilibrium. Non-equilibrium phenomena are all around us and range from weather patterns to life itself. Two important aspects of systems out of equilibrium are: (1) stationary states, wherein the system will remain if not pushed from the outside, and (2) the relaxation towards these stationary states. Gaining a better understanding of both the stationary properties and the relaxation processes are needed in order to fully understand the world around us, and to develop new ways to manipulate these processes to tailor the properties of materials and other systems.The study of interacting systems of many particles far from equilibrium poses challenges, on both the fundamental and the practical level. While there is a well established theoretical framework for equilibrium systems, a similar comprehensive framework remains elusive for non-equilibrium systems and processes. The PI will exploit a variety of theoretical and computational techniques to advance our understanding of non-equilibrium phenomena. The PI aims to develop new interdisciplinary approaches, that combine statistical physics with advanced theoretical techniques from other areas of physics, and to advance understanding of the influence surfaces and interfaces on non-equilibrium processes. The PI aims to investigate aging phenomena through the study of model systems that are representative of large classes of condensed matter systems. Aging phenomena have been exploited since prehistoric times to optimize some materials so that they achieve desired properties. This project is designed so that both undergraduate and graduate students can contribute in a substantial and meaningful way, using a variety of methods. This training through research approach allows students to be involved at every level in cutting-edge research projects.

该奖项支持远离平衡的相互作用多粒子系统的理论研究和教育。PI将结合联合收割机先进的分析和数值技术，探索远离平衡的瞬态和稳态特性的新方面。将进行两项主要的研究。第一个重点是远离平衡的弛豫过程。对数增长系统中的老化现象仍然知之甚少，即使许多重要的无序系统预计将显示这种类型的缓慢增长在很长的时间限制。PI试图通过研究范式模型来获得对衰老的新见解，这些模型适用于数值和分析方法。 受最近人工反铁磁体老化实验的启发，PI计划将弛豫研究扩展到复杂性不断增加的分层伊辛系统。更好地了解这些系统中的老化过程，将有助于建立人工反铁磁体作为非无序系统中非平衡过程实验研究的新范式。PI的目标是建立在最近的工作，表明老化现象和引力物理之间存在的二元性，以进一步打开非平衡物理领域的弦理论技术。第二个推力集中在非平衡相变发生在非均匀系统的表面和边界的影响不能忽略。PI将研究在表面或边界处输入能量的两种不同非均匀系统中的相变：（1）具有磁摩擦的有界系统和（2）具有守恒动力学的系统，其中不同的扇区与不同的热浴接触。所观察到的结果，从新颖的表面相变的出现对流细胞和温度驱动的条纹相之间的过渡，值得深入研究，以充分了解相变系统与本地能量输入。部分由于自然界中普遍存在的非平衡过程，这项研究有可能跨越学科界限产生影响。这个项目的设计，使本科生和研究生都可以在一个实质性的和有意义的方式作出贡献，使用各种各样的方法。这种通过研究方法进行的培训使学生能够参与尖端研究项目的各个层面。非技术性总结该奖项支持理论研究和教育，这些理论研究和教育涉及许多远离稳定平衡态的相互作用粒子系统中发生的现象。非平衡现象就在我们身边，从天气模式到生命本身。系统脱离平衡的两个重要方面是：（1）稳态，其中系统如果不被外界推动，将保持不变，以及（2）向这些稳态的弛豫。为了更好地理解我们周围的世界，需要更好地理解定态性质和弛豫过程，并开发新的方法来操纵这些过程，以定制材料和其他系统的性质。远离平衡的许多粒子的相互作用系统的研究在基础和实践层面上都提出了挑战。虽然有一个完善的平衡系统的理论框架，一个类似的全面的框架仍然难以捉摸的非平衡系统和过程。PI将利用各种理论和计算技术来加深我们对非平衡现象的理解。PI旨在开发新的跨学科方法，将联合收割机统计物理学与物理学其他领域的先进理论技术相结合，并促进对非平衡过程的影响面和界面的理解。PI旨在通过研究代表大类凝聚态系统的模型系统来研究老化现象。自史前时代以来，人们就利用老化现象来优化某些材料，使其达到所需的性能。这个项目的设计，使本科生和研究生都可以在一个实质性的和有意义的方式作出贡献，使用各种方法。这种通过研究方法的培训使学生能够参与尖端研究项目的各个层面。