Collective Phenomena in Random Media

9985978 ZimanyiThis赠款继续NSF支持的两个职业生涯中期PI的从加州大学戴维斯分校的合作工作。 他们的工作，集体行为的强相互作用的多体系统在无序的存在下，结合分析和数值方法来解决当前感兴趣的各种问题。 本研究有三个相关计画：（1）高Tc氧化物超导体，特别是层状效应最强的材料中的涡旋性质。 (2)在无序超导体中寻找玻色金属相。 本计画亦将研究二维金属-绝缘体转变中库仑相互作用与无序之间的相互作用，并探讨非自平均系统中逾渗效应的作用。 最后，项目（3）包括对记录介质中滞后现象的广泛研究。 早期的结果表明，在现实版本的谢灵顿-柯克帕特里克模型的自组织临界性的持久性。 在这些模型中，老化、畴成核、畴壁扩展和雪崩形成等效应可能起着重要作用。这笔赠款继续NSF支持的两个职业生涯中期PI的从加州大学戴维斯分校的合作工作。 这些PI的工作对当前感兴趣的各种问题，从高温超导体的磁记录介质的属性。 在前者中，他们继续详细探索磁场对超导特性的微妙影响。 他们特别感兴趣的是，在系统中，这些效果的增强更像层。 在磁记录介质中，他们计划进一步探索他们从模型计算中得出的早期结果，这些结果表明存在“自组织临界性”。

9985978ZimanyiThis grant continues the NSF support of the collaborative work of two mid-career PI's from UC Davis. Their work, on collective behavior of strongly interacting many-body systems in the presence of disorder, combines analytical and numerical approaches to a variety of problems of current interest. There are 3 related projects: (1) Properties of vortices in high Tc Oxide superconductors, especially those materials where the layering effects are most strongly present. (2) A search will be carried out for a Bose metal phase in disordered superconductors. This project will also involve a study of the interplay between Coulomb interaction and disorder in 2-d metal-insulator transition and explore the role of percolation effects in non-self-averaging systems. Finally project (3) consists of an extensive study of the hysteretic phenomena in recording media. Early results indicate persistence of self-organized criticality in realistic versions of Sherrington-Kirkpatrick models. It may be that in these models, such effects as aging, domain nucleation, domain wall propagation and avalanche formation play an essential role.%%%This grant continues the NSF support of the collaborative work of two mid-career PI's from UC Davis. These PI's work on a variety of problems of current interest, ranging from high Tc superconductors to properties of magnetic recording media. In the former, they are continuing with a detailed exploration of subtle effects of magnetic field on the superconducting properties. They are, in particular interested in the enhancement of these effects in systems which are more layer-like. In the magnetic recording media, they plan to further explore their early results from model calculations which show the presence of "self-organized criticality".***