CAREER: Electrical and Thermoelectric Transport Beyond the Metal/Insulator Paradigm

职业：超越金属/绝缘体范式的电和热电传输

• 批准号: 2045742
• 负责人: Brian Skinner
• 金额: $ 50.54万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045742&HistoricalAwards=false
• 关键词: CAREER; Electrical; Thermoelectric; Transport; Beyond

Nontechnical AbstractElectronic materials are traditionally dichotomized into two broad classes: metals and insulators. In this dichotomy, metals are materials that can conduct electricity via a "Fermi surface" of electrons, and insulators are materials that do not conduct electricity and have no such Fermi surface. But the last decade has uncovered whole new classes of materials, "topological materials," that defy the established dichotomy. Topological materials are able to conduct electricity but have no Fermi surface of electrons. The possibilities for new technology and new physical phenomena inherent in this combination of properties remain largely to be explored.This award supports an integrated plan of research, outreach, and education. The research activities aim to explore, theoretically, the possibilities for new bulk phenomena in topological materials. The research focuses in particular on thermoelectric properties (the conversion of heat to electric power) and on the nature of the transition from conducting to non-conducting states. Key questions include these: 1) which conditions and which materials are conducive to achieving an efficient conversion of heat to electric power?, and 2) what new forms of the metal-to-insulator transition are possible, and what are their experimental signatures?New topological thermoelectric materials may have applications in both waste-heat recovery and more efficient cooling. Understanding new forms of the metal-insulator transition could lead to new generations of electronic devices.The outreach and education activities make concrete steps toward improving the visibility and accessibility of condensed matter physics as a field, and toward broadening participation within it. Activities include (i) developing lesson plans that introduce electricity and electric materials to elementary school students in underserved communities, (ii) developing problem sets and lectures for the community of high school students participating in olympiad-level physics competitions, (iii) building an inclusive research group and developing new courses at the graduate and undergraduate level, (iv) mentoring students from underrepresented demographic groups through the Bridge Program at Ohio State University, and (v) developing social media content that introduces condensed matter physics to the public.Technical AbstractThis award supports an integrated plan of research, outreach, and education that is based on the transport properties of electronic materials. The research focuses primarily on topological materials, which harbor the possibility for fundamentally new kinds of transport properties and electronic phases compared to those possible in traditional metals and insulators. Exploring these possibilities requires theories that go beyond the non-interacting, free-particle descriptions that led to the discovery and classification of topological materials. The aim of this research is to produce such theories, focusing in particular on bulk thermoelectric transport and on the nature of the metal-insulator transition.One thrust of the research is concerned with the thermoelectric response of topological semimetals and its dependence on magnetic field. The PI and his research team will consider magnetic Weyl semimetals, compensated topological semimetals, and other topological materials beyond Dirac/Weyl. The goal of this work is to identify conditions and material properties that are conducive to achieving large thermopower and large thermoelectric efficiency. A second thrust considers how topological systems admit novel bulk metal-insulator transitions, beyond the canonical Anderson and Mott perspectives. The research team will consider different scenarios for such transitions, including in strongly disordered systems, hydrodynamic systems, and in electron systems with nonperturbative electron-phonon coupling. The goal of these works is to uncover possible new electronic quantum phenomena, which have strong manifestations in the electrical conductivity, and to illustrate how they may appear in real materials.Integrated with these research efforts is a comprehensive plan for outreach and education that will take concrete steps toward improving the visibility and accessibility of condensed-matter physics as a field, and toward broadening participation within it. Activities include (i) developing lesson plans that introduce electricity and electric materials to elementary school students in underserved communities, (ii) developing problem sets and lectures for the community of high-school students participating in olympiad-level physics competitions, (iii) building an inclusive group and developing new courses at the graduate and undergraduate level, (iv) mentoring students from underrepresented demographic groups through the Bridge Program at Ohio State University, and (v) developing social media content that introduces condensed-matter physics to the public.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.

电子材料传统上分为两大类：金属和绝缘体。 在这种二分法中，金属是可以通过电子的“费米面”导电的材料，而绝缘体是不导电且没有这种费米面的材料。 但在过去的十年里，人们发现了全新的材料类别，即“拓扑材料”，它挑战了既定的二分法。 拓扑材料能够导电，但没有电子的费米表面。 新技术的可能性和新的物理现象固有的这种组合的属性仍然在很大程度上有待探索。这个奖项支持研究，推广和教育的综合计划。 研究活动旨在从理论上探索拓扑材料中新的体现象的可能性。 该研究特别侧重于热电性能（热量转换为电能）和从导电状态到非导电状态的过渡性质。 关键问题包括：1）哪些条件和哪些材料有利于实现热到电能的有效转换？2）金属-绝缘体转变可能有哪些新形式，它们的实验特征是什么？新的拓扑热电材料可能在废热回收和更有效的冷却方面都有应用。 了解金属-绝缘体转变的新形式可能会导致新一代的电子设备。推广和教育活动为提高凝聚态物理学作为一个领域的可见性和可及性以及扩大参与范围迈出了具体步骤。活动包括（i）制定课程计划，向服务不足社区的小学生介绍电力和电气材料，㈡为参加奥林匹克级物理竞赛的高中生群体编制问题集和讲座，㈢建立一个包容性的研究小组，并在研究生和本科生一级开发新课程，㈣通过俄亥俄州州立大学的桥梁方案指导代表性不足的人口群体的学生，以及（v）开发向公众介绍凝聚态物理的社交媒体内容。技术摘要该奖项支持基于电子材料传输特性的研究，推广和教育的综合计划。 该研究主要集中在拓扑材料上，与传统金属和绝缘体相比，拓扑材料具有全新的传输特性和电子相。 探索这些可能性需要超越非相互作用、自由粒子描述的理论，这些理论导致了拓扑材料的发现和分类。 本研究的目的是产生这样的理论，特别是集中在体热电输运和金属-绝缘体transition.One推力的研究的性质是关注的拓扑半金属的热电响应和它对磁场的依赖。 PI和他的研究小组将考虑磁性Weyl半金属，补偿拓扑半金属和其他拓扑材料超越Dirac/Weyl。 这项工作的目标是确定有利于实现大的热功率和大的热电效率的条件和材料特性。 第二个推力考虑拓扑系统如何承认新的大块金属-绝缘体转变，超越了典型的安德森和莫特的观点。 研究小组将考虑这种转变的不同情况，包括在强无序系统，流体动力学系统和具有非微扰电子-声子耦合的电子系统中。 这些工作的目标是揭示可能的新的电子量子现象，这些现象在电导率中有很强的表现，并说明它们如何在真实的材料中出现。与这些研究工作相结合的是一个全面的推广和教育计划，将采取具体步骤，提高凝聚态物理学作为一个领域的可见性和可及性，活动包括：（i）制定课程计划，向服务水平低下社区的小学生介绍电力和电力材料，（ii）为参加奥林匹克级物理竞赛的高中生社区制定问题集和讲座，（iv）通过俄亥俄州州立大学的桥梁方案，指导来自代表性不足的人口群体的学生，以及（v）开发社交媒体内容，该奖项反映了NSF的法定使命，并通过使用基金会的智力价值进行评估，更广泛的影响审查标准。

项目成果

Conductivity of Two-Dimensional Small Gap Semiconductors and Topological Insulators in Strong Coulomb Disorder

• DOI: 10.1134/s1063776122100065
• 发表时间: 2022-01
• 期刊: Journal of Experimental and Theoretical Physics
• 影响因子: 1.1
• 作者: Y. Huang;B. Skinner;B. Shklovskii

Wigner crystallization at large fine structure constant

• DOI: 10.1103/physrevb.106.l041402
• 发表时间: 2021-10
• 作者: S. Joy;B. Skinner

Upper bound on the window of density occupied by microemulsion phases in two-dimensional electron systems

二维电子系统中微乳液相占据的密度窗口上限

• DOI: 10.1103/physrevb.108.l241110
• 发表时间: 2023
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Joy, Sandeep;Skinner, Brian
• 通讯作者: Skinner, Brian

Conductivity of two-dimensional narrow gap semiconductors subjected to strong Coulomb disorder

• DOI: 10.1103/physrevb.105.054206
• 发表时间: 2021-11
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Yi Huang;Yanjun He;B. Skinner;B. Shklovskii

Doping as a tuning mechanism for magnetothermoelectric effects to improve zT in polycrystalline NbP

• DOI: 10.1103/physrevb.107.115108
• 发表时间: 2022-06
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: E. F. Scott;Katherine A. Schlaak;Poulomi Chakraborty;C. Fu;S. Guin;Safa Khodabakhsh;A. Paz y Puente-A.-Paz-y