Multiscale Computational Design of Active Thermal Interfaces Leveraging Quantum Phenomena

研究综述：该项目提出了(1)基于纳米和原子尺度上活跃的量子力学共振能量交换机制的界面热能传输的新概念，以及(2)开发了一个多尺度计算框架来评估这种界面的潜力和优化设计。传统上，界面导电性是通过被动机制实现的，依靠声子匹配来辅助两个表面的导电性。相反，该项目建议研究表面之间的一种额外的能量交换机制，这种机制是由连接到两个表面的分子层之间的共振偶极-偶极相互作用所介导的。所探讨的界面概念是固体和分子吸附体之间的电子和振动能量交换机制，以及近距离两个表面之间的电子能量交换机制。评估和优化设计需要将热传输中的多个尺度联系起来，从埃量子尺度到亚微米声子平均自由程尺度。智能优点：人们普遍认为，传统的固体-固体热传导为界面上的热传递提供了最佳选择。这项工作将严格地研究有源界面设计是否具有增强固体-固体极限以外的热传导的潜力。所提出的界面设计将许多活跃的现象链接在不同的长度尺度上，并且内在地需要多尺度的方法。这些将要实现的技术包括第一性原理方法(密度泛函理论、量子蒙特卡罗)、分子动力学模拟和基于麦克斯韦方程的连续能级模拟。该团队由两名活跃的研究人员组成，他们研究纳米尺度的传输现象和材料的第一原理建模。更广泛的影响：在包括微电子和大规模应用在内的各种领域，接口是热传输的限制因素。这一建议考虑了一种基于共振能量传递过程的界面热传导的全新的、潜在的变革性方法。这里提出的研究还将得到一些协同教学活动的补充：(1)创建一系列六个Java小应用程序，题为“界面纳米热传输”，旨在用作大学一级的教学工具，将通过PI网站和通过在教育期刊上发表向教育工作者提供。(2)拟议的研究将为纳米科学、传输现象和多尺度建模等多学科领域的两名研究生提供培训和发展的机会。(3)本科生研究人员将参与并接触到这一新的研究领域。(4)在项目期间，PIS将协调一个全天的研讨会，包括建模演示、实验室参观和动手活动，该研讨会将在每年夏天在伊利诺伊大学校园女子中学举行的GIRRLS探索科学和工程夏令营期间举行。(5)研究结果将在同行评议的档案期刊上传播，并在会议上介绍。

#1250192SinhaResearch Summary: The project proposes (1) a new concept for interfacial thermal energy transport based on quantum mechanical resonant energy exchange mechanisms active at the nano and atomic scale, and (2) the development of a multiscale computational framework to assess the potential and optimize the design of such an interface. Traditionally, interfacial conductivity is engineered by passive mechanisms, relying on phonon matching to assist conductional across two surfaces. Instead, the project proposes to investigate an additional energy exchange mechanism between the surfaces mediated by resonant dipole-dipole interactions between molecular layers bonded to the two surfaces. The interface concepts explored are electronic and vibrational energy exchange mechanism between a solid and molecular adsorbates, and electronic energy exchange mechanisms between two surfaces in close proximity. Assessing and optimizing the design requires linking multiple scales in thermal transport from angstrom quantum scales to sub-micrometer phonon mean free path scales. Intellectual Merit: It is commonly believed that conventional solid-solid heat conduction offers the best option for thermal transfer across an interface. This work will critically investigate whether active interface design has the potential for enhanced thermal conduction beyond the solid-solid limit. The interface design proposed links a numbers of active phenomena operative at variety of length scales, and inherently requires a multiscale approach. These techniques to be implemented include first-principles methods (density functional theory, quantum Monte Carlo), molecular dynamics simulations, and continuum level modeling based on Maxwell's equations. The team consists of two active researchers in nanoscale transport phenomena and in first-principles modeling of materials. Broader Impact: Across a variety of arenas including microelectronics and large scale applications, interfaces are the limited factor for heat transport. This proposal considers a fundamentally new and potentially transformative approach to interfacial thermal conductional based on resonant energy transfer processes. The research proposed here will also be complemented by a number of synergistic teaching activities: (1) Creating a series of six java applets entitled Nanoscale Thermal Transport at Interfaces meant for use as a university-level teaching tool, that will be made available to educators via PI websites and through publication in an education journal. (2) The proposed research will provide the opportunity for the training and development of two graduate students in the multidisciplinary fields of nanosciences, transport phenomena, and multiscale modeling. (3) Undergraduate researchers will be involved and exposed to this new field of study. (4) For the duration of the program, the PIs will coordinate a full-day workshop, including modeling demonstrations, laboratory tours, and hands-on activities, to take place during the GIRRLS Exploring Science and Engineering Camp, held every summer at the University of Illinois Campus Middle School for Girls. (5) The research findings will be disseminated in peer-reviewed, archival journals and presented at conferences.