Correlated Quantum Systems: Topological Phases, Non-Fermi-liquids and Entanglement

相关量子系统：拓扑相、非费米液体和纠缠

• 批准号: RGPIN-2016-03977
• 负责人: Metlitski, Max
• 金额: $ 2.4万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=614758
• 关键词: Correlated; Quantum; Systems; Topological; Phases

The aim of my research program is to understand the different ways that electrons can organize themselves in solids. Amazingly, the basic laws of quantum mechanics, together with simple electrostatic interactions governing electron motion, give rise to a great array of different phases of matter, such as metals, insulators, superconductors, and magnets. In the last ten years, an entirely new class of phases of matter was discovered: topological insulators. The bulk of these materials does not conduct electricity, however the surface does. One may think that this is an accident and that one can cut the conducting surface layer away, but in fact, any cleave of the bulk material always exposes a new conducting surface. A primary goal of my research program is to classify all such bulk topological insulators and related phases of matter and to understand their surface behaviour. This direction of research addresses fundamental questions at the forefront of solid state physics, provides a link to active areas in modern mathematics, such as topology and category theory, and furthermore, paves the way for technological applications of topological phases of matter in quantum computing. Aside from studying exotic insulators, I am also pursuing unusual conductors (metals). Simple metals, like copper, are very successfully described by Landau Fermi-liquid theory, however, there are a number of materials, collectively referred to as “strange metals,” whose behaviour strongly deviates from Fermi-liquid theory. These include cuprate, iron-arsenic and certain heavy-fermion material families. Like simple metals, strange metals often turn superconducting when the temperature is lowered below a critical temperature Tc; however, the magnitude of Tc is often much higher than in simple metals. A goal of my research program is to develop a theory of strange metals and their superconducting instabilities - a necessary first step in the long-term effort to systematically design new materials with high superconducting Tc for application purposes.

我的研究计划的目的是了解电子在固体中组织自己的不同方式。令人惊讶的是，量子力学的基本定律，加上控制电子运动的简单静电相互作用，产生了大量不同相的物质，如金属、绝缘体、超导体和磁体。在过去的十年里，人们发现了一种全新的物质相：拓扑绝缘体。这些材料的大部分不导电，但表面导电。人们可能会认为这是一个意外，可以切掉导电表面层，但事实上，任何分裂的大块材料总是暴露出一个新的导电表面。 我的研究计划的一个主要目标是对所有这些大块拓扑绝缘体和相关的物质相进行分类，并了解它们的表面行为。这个研究方向解决了固态物理学前沿的基本问题，提供了与现代数学中活跃领域的联系，如拓扑学和范畴论，并为量子计算中物质拓扑相的技术应用铺平了道路。 除了研究奇异的绝缘体，我也在研究不寻常的导体（金属）。简单的金属，如铜，被朗道费米液体理论非常成功地描述，然而，有一些材料，统称为“奇怪的金属”，其行为强烈偏离费米液体理论。其中包括铜酸盐、铁砷和某些重费米子材料家族。与简单金属一样，当温度低于临界温度Tc时，奇异金属通常会变成超导体;然而，Tc的大小通常比简单金属高得多。我的研究计划的一个目标是发展一个理论的奇怪的金属和超导不稳定性-必要的第一步，在长期的努力，系统地设计新材料与高超导Tc的应用目的。