Statistical Mechanics of Driven Diffusive Systems

驱动扩散系统的统计力学

• 批准号: 9419393
• 负责人: Beate Schmittmann
• 金额: $ 39万
• 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: 1995
• 资助国家: 美国
• 起止时间: 1995-01-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9419393&HistoricalAwards=false
• 关键词: Statistical; Mechanics; Driven; Diffusive; Systems

9419393 Schmittmann Though there has been significant recent progress in the understanding of the co-operative behavior of driven diffusive systems, a host of new questions and surprising discoveries have also appeared. These puzzling issues will be addressed, from readily achievable goals to long-term projects. The former include (i) continued studies of uniformly and randomly driven systems, focusing on global features of the phase diagram and detailed properties like critical singularities, (ii) further exploration of multi-species and multi-layer systems, and (iii) theoretical understanding of interfacial instabilities and anomalous correlations. The latter is concerned with some fundamental questions, e.g., methods for simulating quenched impurities in finite systems with global currents, the existence of essential singularities at first order transitions far from equilibrium, and the role of detailed balance. %%% An exciting and rapidly expanding area in condensed matter physics is the study of complex co-operative behavior in systems driven far from equilibrium. Prominent examples include self-organized critically and driven diffusive systems. Since non-equilibrium phenomena are abundant in nature, it is clearly important that they be well understood, both in terms of theoretical foundations and practical applications. A promising approach consists of investigating simple models which retain the essential characteristics of these systems. Using an interplay of computer simulations and analytic methods, specific studies on such models is proposed, with a view to a wide range of potential applications, e.g., gel electrophoresis, intercalation processes, flow patterns of granular materials or traffic, flux creep in superconductors, biased diffusion on surfaces, and the dynamics of fracture.

虽然最近在理解驱动扩散系统的合作行为方面取得了重大进展，但也出现了许多新的问题和令人惊讶的发现。这些令人困惑的问题将得到解决，从容易实现的目标到长期项目。前者包括(i)对均匀和随机驱动系统的持续研究，重点关注相图的全局特征和临界奇点等详细性质；（ii）对多物种和多层系统的进一步探索；（iii）对界面不稳定性和异常相关性的理论理解。后者涉及一些基本问题，例如，模拟具有全局电流的有限系统中淬火杂质的方法，远离平衡的一阶跃迁的本质奇点的存在，以及详细平衡的作用。凝聚态物理中一个令人兴奋和迅速发展的领域是对远离平衡态的系统的复杂合作行为的研究。突出的例子包括自组织临界和驱动扩散系统。由于自然界中存在着大量的非平衡现象，因此从理论基础和实际应用两方面对它们进行充分理解显然是很重要的。一个有希望的方法是研究保留这些系统基本特征的简单模型。利用计算机模拟和分析方法的相互作用，提出了对这些模型的具体研究，以期广泛的潜在应用，例如凝胶电泳，插层过程，颗粒材料或交通的流动模式，超导体中的通量蠕变，表面上的偏扩散以及断裂动力学。