Controlling Quantum Materials: Exotic Orders and Light-Induced Dynamics

控制量子材料：奇异的秩序和光致动力学

• 批准号: RGPIN-2021-03214
• 负责人: Paramekanti, Arun
• 金额: $ 2.99万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762708
• 关键词: Controlling; Quantum; Materials; Exotic; Orders

What principles governs the collective quantum behaviour of electrons in a crystalline solid? Can one tune quantum phases of electrons by controlling dimensionality? Can light be used to control and switch between many-body quantum states of electrons? Exploring these important issues is crucial to gain a fundamental understanding of quantum condensed matter systems, and it holds the key to creating and controlling quantum materials which can lay the foundation for the next generation of quantum technologies. The equilibrium and dynamical properties of electrons in crystals are governed by the laws of quantum mechanics, together with quantum statistics as encoded in the Pauli exclusion principle. Examples of such crystals, which include silicon, the workhorse of the semiconductor industry, are extremely well-understood within the framework of band theory and Fermi liquid theory. However, when strong electron interactions become important in a crystal, the electrons can organize into remarkable new states leading to superconductivity, colossal magnetoresistance, or electronic liquid crystals. Transition metal oxides provide a canonical example of such ``emergent'' behavior, exhibiting a plethora of new collective phases, with a slew of applications such as solid state drives, catalysts, and photovoltaics. In recent years, it has been recognized that relativistic spin-orbit coupling can impart new topological character to electronic bands in solids with the potential for novel devices and the promise of new directions in the field of quantum computing. The five-year research programme outlined in this proposal focuses on two intertwined threads of research. The first thread aims to explore and understand the optical properties of exotic orders which appear in quantum materials such as heavy transition metal oxides, halides, and chalcogenides. These are quantum materials which exhibit strong atomic spin-orbit coupling, which leads to the emergence of topological phases, unconventional superconducting and magnetic orders, both in bulk crystals as well in two-dimensional thin films and interfaces. The second intertwined thread of the research deals with how one might control and manipulate such quantum materials and their electronic phases using light. The proposed research will focus on optical properties such as THz conductivity and Kerr effects, ultrafast pump-probe dynamics, and switching between electronic states of matter using optically driving of phonon modes. The proposed research will utilize numerical tools including Gutzwiller projected wavefunction techniques, high frequency expansions, strong coupling expansions, and novel methods to treat the dynamics of correlated electrons.

哪些原理控制着晶体固体中电子的集体量子行为？可以通过控制尺寸的电子量子相吗？可以使用光来控制和切换电子的量子状态吗？探索这些重要问题对于获得对量子凝结物质系统的基本了解至关重要，并且它是创建和控制量子材料的关键，这可以为下一代量子技术奠定基础。晶体中电子的平衡和动力学特性受量子力学定律的控制，以及保利排除原理中编码的量子统计。这些晶体的例子，包括硅（包括半导体行业的主力），在乐队理论和费米液体理论的框架内非常被理解。但是，当强烈的电子相互作用在晶体中变得重要时，电子可以组织成显着的新状态，从而导致超导性，巨大的磁性或电子液体晶体。过渡金属氧化物提供了这种``新兴''行为的规范示例，表现出了许多新的集体阶段，并具有许多应用，例如固态驱动器，催化剂和光伏。近年来，人们已经认识到，相对论的自旋轨道耦合可以将新的拓扑特征传授给具有新型设备潜力和量子计算领域新方向的希望的固体中的电子带。该提案中概述的五年研究计划重点介绍了两个相互交织的研究线程。第一个线程旨在探索和理解出现在量子材料（例如重型金属氧化物，卤化物和辣椒剂）中的外来秩序的光学特性。这些是量子材料，表现出强大的原子自旋轨道耦合，从而导致拓扑阶段，非常规的超导和磁性的出现，包括在二维薄膜和界面中的散装晶体。研究的第二个互动线程涉及人们如何使用光控制和操纵这种量子材料及其电子相。拟议的研究将着重于光学特性，例如THZ电导率和KERR效应，超快泵浦探针动力学以及使用声子模式的光学驱动器之间的电子状态之间的转换。拟议的研究将利用数值工具，包括Gutzwiller投影的波函数技术，高频扩展，强耦合扩展以及新的方法来处理相关电子的动力学。