Collaborative Research: Wave transport via eigenchannels of complex media

与半透明介质中的视线传播一样，光在不透明介质中的传输是一种看似随机的游走，可以用扩散过程来描述。常见的电子，声学，以及电磁波，大部分的入射波被反射，只有一小部分是通过众多的部分波传输具有宽范围的延迟时间。与直觉相反，这种行为可以通过利用波干涉来改变。该奖项支持一项实验和理论工作，以研究在芯片级平台上操纵输入波的程度，以实现近100%的传输或避免短脉冲的时间传播。耶鲁大学的一个实验小组和密苏里科技大学的一个理论小组的合作项目将训练研究生和本科生在多个领域的不断发展的边界上进行跨学科研究，包括凝聚态物理、复杂介质的光学、纳米技术和计算物理。前沿研究将被纳入两个参与机构的课程。该项目包括一个广泛的交流项目，包括教师和学生的访问、暑期实习、为本科生研究项目设计和组装光学演示以及招聘活动。摘要传输本征信道的概念是介观物理学的基础，它同样适用于电磁波和声波。尽管本征通道在介观传输中的重要作用以及光学/声学成像应用的巨大机会，但人们对单个传输本征通道或时延本征通道的内在特性知之甚少。这个合作项目支持在一个独特的片上光子平台上对单个本征通道的统计特性进行联合实验和理论研究，例如它们的波动和相关性，该平台允许光选择性地耦合到单个本征通道中，并直接探测其在随机介质中的空间结构。与电子系统相比，室温下光子相干效应的鲁棒性使光学系统成为深入研究相干波输运基础的理想选择。提出的工作解决了介观物理学中长期存在的问题，即个体传输和时滞特征通道的性质和统计特性，以及它们在静态和动态波输运中所起的作用。实验和数值结果之间的系统比较将提供关键的见解，以了解特征通道是如何形成的，是什么决定了它们的性质，以及是否有可能同时实现波传输的时空控制。该研究计划将产生广泛的实验和数值数据，这将为介观物理界开发和验证相干波输运的新理论模型铺平道路。在光学领域，对通过本征信道的相干传播的基本理解将为广泛的实际应用提供信息，从激光手术、光伏、浑浊介质成像到随机激光和节能环境照明。这个实验-理论合作项目将培养研究生和本科生在多个领域进行跨学科研究，包括凝聚态物理、复杂介质光学、纳米技术和计算物理。前沿研究将被纳入两个参与机构的课程。两队将携手开展教育外展活动。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL ABSTRACTUnlike line-of-sight propagation in a translucent medium, light transport in an opaque medium is a seemingly random walk that is described by a diffusion process. Common to electronic, acoustic, as well as the electromagnetic waves, most of the incident wave is reflected, and only a small fraction is transmitted via a multitude of partial waves with a broad range of delay times. Counterintuitively, this behavior can be altered by exploiting wave interference. This award supports an experimental and theoretical efforts to investigate the degree, to which one can manipulate input waves in a chip-scale platform, to achieve near-100% transmission or avoid temporal spread of a short pulse. The collaborative program of an experimental group at Yale University and a theoretical group at Missouri University of Science & Technology will train graduate and undergraduate students to conduct interdisciplinary research across the evolving boundaries of multiple fields, including condensed matter physics, optics of complex media, nanotechnology, and computational physics. The cutting-edge research will be incorporated in the curriculum at both participating institutions. This project includes an extensive exchange program with visits by faculty and students, summer internships, design and assembly of optical demonstrations for undergraduate research projects and recruitment activities.TECHNICAL ABSTRACTThe concept of transmission eigenchannels has been a cornerstone of mesoscopic physics but it is also applicable to electromagnetic waves and acoustic waves. Despite of the essential role of the eigenchannels in mesoscopic transport and vast opportunities for optical/acoustic imaging applications, little is known about the intrinsic properties of individual transmission eigenchannels or the time-delay eigenchannels. This collaborative program supports a joint experimental and theoretical studies on the statistical properties of individual eigenchannels, such as their fluctuations and correlations, in a unique on-chip photonic platform that allows both selective coupling of light into a single eigenchannel and direct probe of its spatial structure inside the random medium. Compared to electronic systems, robustness of coherence effects for photons at room temperature makes optical systems ideal for the in-depth fundamental studies of coherent wave transport. The proposed work addresses long-standing questions in mesoscopic physics regarding the nature and statistical properties of individual transmission and time-delay eigenchannels and the roles they play in static and dynamic wave transport. A systematic comparison between the experimental and numerical results will provide key insights into how the eigenchannels are formed, what determines their properties, and whether it is possible to achieve simultaneously spatial and temporal control of wave transmission. The research program will produce a wide range of experimental and numerical data, which will pave the way for the mesoscopic physics community to develop and verify new theoretical models for coherent wave transport. In optics, the fundamental understanding of coherent propagation via eigenchannels will inform a broad range of practical applications, from laser surgery, photovoltaics, imaging in turbid media, to random laser and energy-efficient ambient lighting. The collaborative experimental-theoretical program will train graduate and undergraduate students to conduct interdisciplinary research across the evolving boundaries of multiple fields, including condensed matter physics, optics of complex media, nanotechnology, and computational physics. The cutting-edge research will be incorporated in the curriculum at both participating institutions. The two teams will join force in education outreach activities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.