Topics in Classical and Quantal Soft Matter

该奖项支持在经典和量子软物质统计物理学中一系列相互关联的主题的理论研究和教育。它的两个主要部分集中于(i)通过硫化形成的软随机固体介质的结构和弹性，特别是在成分容易结晶的环境中；（ii）非平衡原子-光共结晶及其对限于多模光学腔的激光驱动超冷原子的影响——PI称之为“软量子物质”的主题。该项目的相关要素涉及（三）纤维性、强相互作用的聚合物体系及其波动，通过使用量子多体物理学的概念和技术使其易于处理；（iv）细胞外膜的物理性质，这是一个覆盖许多生物细胞的富含聚合物的区域，在细胞的控制下，似乎在重要的细胞功能中起着核心作用，包括运动和分裂；(v)可变形胶体粒子系统的液态、晶体和玻璃态行为，这似乎是由粒子的外部构型和它们的内部可变形性之间的相互作用所控制的。在很大程度上，这些主题的灵感来自正在进行的或预期的实验。随机固体是主题(i)的重点，是通过随机选择的成分的永久化学键制成的材料，例如硫化橡胶。这种结合创造了一种新的物质状态，它具有剪切弹性和其成分的空间定位，但没有长程结晶性。PI的目的是发展对母液在其多种形式中表现出长期或短期液态结晶度时出现的定性新特征的理解。这个顺序影响随机固体结构，也受随机固体结构的影响。为了实现这些目标，统计机械工具将被应用于适当地解释这些材料所呈现的随机性的许多层次。主题（ii）涉及激光驱动的原子气体，被困在高精细光学腔中。这些系统预计将经历令人着迷的非平衡相变到原子之间的自发组织状态，这些原子自洽地填充某些腔辐射模式的偶反节点或奇反节点。对于适当设计的空腔，这些跃迁预计会伴随着原子组织的强烈波动，这些波动会在从空腔泄漏的光的空间和时间相关性上留下印记。PI的目的是开发一个完整的图像的有序，它的稳态波动和丰富的动力学，通过这种非平衡稳态实现。它们的多重随机性，热的，淬灭的和突发的，使得理解硫化介质非常具有挑战性。理解它们的进展，特别是当它们也具有液态结晶性时，继续需要创造精致的概念和强大的技术。超冷原子/激光系统能够激发通常与硬凝聚态物质相关的量子粒子动力学的新实现。基于多模腔的设置为量子软物质和量子非平衡相变开辟了新的前景，其中光学晶格现在是一个涌现的实体，例如，能够结晶/熔化，并支持激发和缺陷。这项关于随机固体和软量子物质的研究可能会对超出其预期领域和直接目标的其他科学领域产生影响。该奖项支持软材料和物质领域的理论研究和教育。PI旨在识别和理解软材料和软物质中的紧急行为。紧急行为产生于组成原子或分子的集体组织或行动。例子包括晶体的弹性、磁性和液体的结晶性。液晶是一类令人着迷的软材料，具有丰富多样的内部结构，分子的空间排列不如固体晶体有组织，但具有由组成分子的方向形成的定向模式。因此，它们可以表现出介于液体和晶体之间的一系列相。这个项目的核心是涉及紧急行为的两个特定主题。第一种是针对软随机固体，比如那些通过固特异的硫化过程形成的固体，在这些固体中，长而灵活的大分子随机地结合在一起，形成一个无序的、颤抖的巨大结构。PI问：这样的媒体有什么属性？尽管它们明显很复杂，如何理解和建模它们呢？它们真的是固体吗？如果是的话，又怎么会是固体呢？因为它们的内部结构与我们熟悉的固体（比如铜或石英）如此不同？通过硫化产生的介质，如橡胶，已经生产了170多年。然而，直到最近，人们才意识到，将硫化与液晶性混合可以产生显著的、定性的新材料——液晶弹性体——PI旨在了解这种材料，这种材料具有令人惊讶的、丰富的和有价值的性质。第二个主题还涉及新的集体行为，由组织和运动的变化引发，这些变化源于强烈的相互作用。其组成部分是原子，在高度抛光的镜子之间以极低的温度保存，并用激光照射。最近人们认识到，这样的系统可以经历一种新的结晶过程，在这种过程中，原子与光结成伙伴，在空间中相互帮助。PI的目标是回答：什么样的原子光晶体是这样被创造出来的，它们与传统的晶体介质有什么关系，它们能教给我们什么关于其他现象的知识——如结晶性和玻璃性？

TECHNICAL SUMMARYThis award supports theoretical research and education on a suite of inter-related topics in the statistical physics of classical and quantal soft matter. Its two major portions focus on (i) the structure and elasticity of soft random solid media formed via vulcanization, especially in settings in which the constituents are prone to liquid crystallinity; and (ii) non-equilibrium atom-light co-crystallization and its consequences for laser-driven ultracold atoms confined to multimode optical cavities - a topic the PI terms "soft quantum matter." Related elements of the project address (iii) systems of fibrous, strongly interacting polymers and their fluctuations, made tractable via the use of concepts and techniques from quantum many-body physics; (iv) the physics of the pericellular coat, a polymer-rich zone that covers many biological cells and, under the control of the cell, seems to play central roles in important cell functions, including motility and division; and (v) the liquid, crystal, and glassy behavior of deformable colloidal particle systems, which appears to be governed by an interplay between the external configurations of the particles and their internal deformability. In large measure these topics are inspired by experiments, either ongoing or anticipated. Random solids, the focus of topic (i), are materials made via the permanent chemical bonding of randomly selected constituents, as exemplified by vulcanized rubber. This bonding creates a new state of matter, which has shear elasticity and spatial localization of its constituents - but with no long-range crystallinity. The PI aims to develop an understanding of the qualitatively new features that arise when the parent liquids exhibit long- or short-range liquid crystallinity in one of its many forms. This order influences and is influenced by the random solid structure. To accomplish these goals, statistical-mechanical tools will be applied to properly account for the many levels of randomness that such materials present.Topic (ii) concerns laser-driven atomic gases, trapped in high-finesse optical cavities. These systems are expected to undergo fascinating non-equilibrium phase transitions to states of spontaneous organization among the atoms, which self-consistently populate either the even or the odd anti-nodes of certain modes of the cavity radiation. For suitably designed cavities, these transitions are expected to be accompanied by strong fluctuations in the atomic organization, which will imprint themselves on the spatial and temporal correlations of the light leaking from the cavity. The PI aims to develop a thorough picture of the ordering, its steady-state fluctuations, and the rich kinetics through which this non-equilibrium steady state is achieved.Their multiple levels of randomness, thermal, quenched, and emergent, make understanding vulcanized media deeply challenging. Progress in understanding them, especially when they also feature liquid crystallinity, continues to demand the creation of refined concepts and powerful techniques. Ultracold atom/laser systems have enabled stimulating new realizations of the dynamics of quantum particles normally associated with hard condensed matter. The multimode cavity-based setting is opening up new vistas - of quantal soft matter and quantum non-equilibrium phase transitions - in which the optical lattice is now an emergent entity, capable, for example, of crystallization/melting, and supporting excitations and defects. This research on random solids and soft quantal matter may have impact on other areas of science beyond its intended domain and immediate goals. NONTECHNICAL SUMMARYThis award supports theoretical research and education in the area of soft materials and matter. The PI aims to identify and understand emergent behavior in soft materials and soft matter. Emergent behavior arises from the collective organization or action of the constituent atoms or molecules. Examples include the elasticity of crystals, magnetism, and liquid crystallinity. Liquid crystals are a fascinating class of soft materials that have a rich variety of internal structures with molecules in spatial arrangements less organized than solid crystals but with directional patterns formed by the orientation of the constituent molecules. So, they can exhibit a range of phases intermediate between liquid and crystalline.Central to this project are two specific themes involving emergent behavior. The first addresses soft random solids, such as those formed via Goodyear's vulcanization process, in which long, flexible macromolecules are bonded together, at random, to form a disordered, quivering, giant structure. The PI asks: What properties do such media have? How can they be understood and modeled, despite their evident complexity? Are they truly solid and, if so, how can this be so, since their internal organization is so different from that of familiar solids, say copper or quartz? Media created via vulcanization, such as rubber, have been manufactured for more than 170 years. However, only relatively recently has it been appreciated that the mingling of vulcanization with liquid crystallinity can produce remarkable, qualitatively new materials - liquid crystalline elastomers - which the PI aims to understand and which have surprising, rich, and valuable properties. The second theme also involves qualitatively new collective behavior, triggered by changes in organization and motion resulting from strong interactions. The constituents are atoms, held at astonishingly low temperatures between highly polished mirrors, and irradiated with laser light. It has recently been realized that such systems can undergo a new kind of crystallization process, in which the atoms partner with the light, assisting one another to organize in space. The PI aims to answer: What kinds of atom-light crystals are thus created, how are they related to conventional crystalline media, and what can they teach us about other phenomena - familiar ones such as crystallinity and glassiness?