EFRI NewLaw: Controlling Thermal Transport with Topologically Guided Heat Carriers

该项目研究基于拓扑热传输新范式的传输，引导和引导热能（热量）的新方法。通过这种范例，可以引导热量仅沿着材料的边界沿着流动，同时避免其内部，以及以高度定向的方式流动，这种方式对材料无序和其他缺陷也是鲁棒的。为了实现这一目标，该团队将利用和设计材料和设备的特殊拓扑特性，涉及各种热载体，包括电子，声子（晶格振动）或光。 该项目的发现和创新可能会影响涉及热能控制和传输的许多技术领域，例如现代电子和光子系统中的片上热管理和冷却，以及通过热电和光热发电的能量产生，转换和收集。该项目还可能导致新的热管理计划，如隔热，？隐形？和定向热流。 该研究小组将为一个名为？热集线器？在NSF资助的NanoHub中，拥有数百万订阅者和用户。该论坛预计将促进分享和交流信息的新兴领域？拓扑热传输有利于纳米级热工程的研究和开发。研究生和本科生都将积极参与该计划的研究和学习活动。将特别注意通过该小组的各种多样性和外联活动扩大少数民族女学生的参与。该项目将利用他们机构的几个现有项目以及与几个本科生和少数民族学院的合作伙伴关系。电子的拓扑状态，如量子霍尔效应（QHE）和拓扑绝缘体（TI）是当代凝聚态物理学中最重要的发展之一。这种拓扑电子状态的特征是沿着绝缘体样品的边界的拓扑保护的电子传输沿着，其不受各种杂质的散射。这个项目将追求拓扑概念，在迄今为止尚未探索的热传输领域。所提出的方法将利用或工程拓扑性质的三种不同类型的热载体？电子、声子和声子极化激元，以实现拓扑引导和保护的热传输，其可以进一步由外力和场控制。 该计划的第一个主题将探索高质量的电子拓扑绝缘体，具有绝缘体和自旋螺旋狄拉克电子的导电拓扑表面状态，以展示光学和磁性控制，非互易电子热传导以及其他由这种拓扑表面电子携带的新型热传输。该项目的第二和第三个主题将集中在电子拓扑状态下的几个关键物理机制的扩展和类似物--例如自旋-动量耦合/锁定，手性/谷态和自旋/谷霍尔效应-声子和混合声子-光子极化激元，以实现各种拓扑声子态和声子/热输运。

This project investigates novel ways to transport, guide and direct thermal energy (heat) based on the new paradigm of topological thermal transport. Through this paradigm, heat can be guided to flow only along the boundary of a material while avoiding its interior, as well as in a highly directional ways that are also robust to material disorder and other defects. To achieve this, the team will harness and engineer special topological properties of materials and devices involving various heat carriers including electrons, phonons (crystal lattice vibrations) or light. Discoveries and innovations from this project could impact many technological areas involving the control and transport of thermal energy, such as on-chip heat management and cooling in modern electronic and photonic systems, as well as energy generation, conversion and harvesting through thermoelectrics and photothermovoltaics. The project could also lead to new schemes for thermal management such as thermal insulation, ?cloaking? and directed thermal flow. The research team will contribute to an online forum called ?Thermal Hub? within NSF-funded NanoHub that counts millions of subscribers and users. The forum is expected to facilitate sharing and exchange of information in the emerging field of ?topological thermal transport?, and benefit research and development in nanoscale thermal engineering in general. Both graduate and undergraduate students will be actively involved in the research and learning activities of the program. Particular attention will be placed on broadening the participation of women & minority students via various diversity and outreach activities by the team. The project will leverage several existing programs at their institutions and partnerships with several undergraduate and minority colleges.Topological states of electrons such as quantum Hall effect (QHE) and topological insulators (TI) are some of the most important developments in contemporary condensed matter physics. Such topological electronic states feature topologically-protected electronic transport along the boundary of an insulating bulk sample that is immune to scattering by various impurities. This project will pursue topological concepts in the so-far-unexplored realm of thermal transport. The proposed approach will harness or engineer topological properties of three different types of heat carriers ? electrons, phonons and phonon-polaritons, to realize topologically guided and protected thermal transport that can be further controlled by external forces and fields. The first theme of the program will explore high-quality electronic topological insulators with insulating bulk and conducting topological surface states of spin-helical Dirac electrons to demonstrate optically and magnetically controlled, and non-reciprocal electronic thermal conduction, and other novel thermal transport carried by such topological surface electrons. The second and third themes of the project will focus on the extension and analogs of several key physical mechanisms underlying the electronic topological states --- such as spin-momentum coupling/locking, chirality/valley states, and spin/valley Hall effects --- to phonons and hybrid phonon-photon polaritons, toward realizing various topological phononic states and phonon/thermal transport.