Coherent Many-Body Quantum States of Matter

相干多体量子物质态

基本信息

批准号：
EP/S020527/1
负责人：
J Chalker
金额：
$ 194.73万
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2019
资助国家：
英国
起止时间：
2019 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FS020527%2F1
关键词：
Coherent Many Body Quantum States

项目摘要

In our everyday life we rarely think about the effects of quantum mechanics --- and yet they are constantly around us, determining the properties of every material object in our world. The laws of quantum physics define every property of matter, from the behaviour of individual atoms, to how the atoms bind together to form materials, to the characteristics of these resultant materials. Our understanding of this chain of influence is one of the greatest triumphs of modern science. It is only through this understanding that scientists have engineered modern technologies and devices such as computers, mobile phones, and fibre-optic communications. In the field of quantum condensed matter, we are concerned with materials, and the quantum mechanics of matter, at a very microscopic scale. Our aim is to uncover new principles, predict new behaviours, new types of matter, and enable new applications. A key concept that we focus on is the idea of quantum mechanical coherence in matter. The word "coherence" here implies that many microscopic objects are acting together in concert. Such behaviour, when it occurs, allows for the effects of quantum physics to be greatly enhanced. A prime example of coherent behaviour occurs in a superconductor, where due to the effects of quantum mechanics, electrons can flow forever with zero resistance and zero energy loss. In the last decades it has become clear in our community that quantum-mechanical coherence in materials is much more common than we previously expected, although its effects are often subtle and well hidden from our view. Understanding coherent effects in systems made of many particles (i.e., in material substances) is the main aim of the research supported by this grant. We use a combination of modern mathematical and computational tools to investigate the puzzles of our field. The physics we study is highly complex because in such systems, the many constituent particles interact strongly with each other. As a consequence, qualitatively different behaviour emerges. Because of the novelty of these effects, this field of study is both challenging and exciting, attracting some of the best and the brightest young scientists. We have divided our effort into three main themes: Understanding Quantum Many-Body Dynamics: the investigation of how quantum mechanics effects the time evolution of material systems on a microscopic scale. We aim to determine new principles for how coherence is created, spreads, and is destroyed, and how this affects the properties of the substance. Exploring Quantum Behaviour Far From the Ground State: for over a century it was believed that if heat energy is put into a physical system at one point, it will inevitably spread out to other regions. In the last few years, however, it has become clear that due to the effects of quantum coherence in interacting disordered systems, added energy may remain localized in one region in a stable fashion. We aim to understand better the properties of systems that present such stable and/or coherent high energy states. Identifying Topological Platforms for Quantum Coherent Phenomena: topological matter exhibits subtle long-range patterns of coherence that cannot be understood by local descriptions. Because of these global effects, such materials are believed to be particularly well suited for robust quantum computing applications. The study of these substances therefore has attracted researchers from physics, mathematics, and computer science. We will explore these materials, where they exist in nature, how they might be engineered, and what their applications are. While our research is mainly academic in nature, we hope that, analogous to discoveries in basic semiconductor physics a century ago, our discoveries may enable technological revolutions of the future.

在我们的日常生活中，我们很少考虑量子力学的影响——但它们却一直在我们身边，决定着我们世界上每个物质对象的属性。量子物理定律定义了物质的每一个属性，从单个原子的行为，到原子如何结合在一起形成材料，再到这些合成材料的特性。我们对这一影响链的理解是现代科学最伟大的成就之一。只有通过这种理解，科学家们才设计出了计算机、移动电话和光纤通信等现代技术和设备。在量子凝聚态领域，我们关注的是非常微观尺度的材料和物质的量子力学。我们的目标是发现新原理、预测新行为、新类型物质并实现新应用。我们关注的一个关键概念是物质中的量子力学相干性的想法。这里的“相干”一词意味着许多微观物体协同作用。当这种行为发生时，量子物理的效应会大大增强。相干行为的一个主要例子发生在超导体中，由于量子力学的影响，电子可以以零电阻和零能量损失永远流动。在过去的几十年里，我们的社区已经清楚地意识到，材料中的量子力学相干性比我们之前预期的要普遍得多，尽管它的影响往往是微妙的，并且很好地隐藏在我们的视野之外。了解由许多粒子（即物质）组成的系统中的相干效应是本次资助支持的研究的主要目标。我们结合使用现代数学和计算工具来研究我们领域的难题。我们研究的物理学非常复杂，因为在这样的系统中，许多组成粒子彼此强烈相互作用。结果，出现了性质不同的行为。由于这些效应的新颖性，这一研究领域既具有挑战性又令人兴奋，吸引了一些最优秀、最聪明的年轻科学家。我们将我们的工作分为三个主题：理解量子多体动力学：研究量子力学如何在微观尺度上影响材料系统的时间演化。我们的目标是确定相干性如何创建、传播和破坏的新原理，以及它如何影响物质的特性。探索远离基态的量子行为：一个多世纪以来，人们一直相信，如果热能在某一点被放入物理系统中，它将不可避免地扩散到其他区域。然而，在过去几年中，人们已经清楚地意识到，由于相互作用的无序系统中量子相干性的影响，增加的能量可能以稳定的方式保持在一个区域。我们的目标是更好地了解呈现这种稳定和/或相干高能态的系统的特性。识别量子相干现象的拓扑平台：拓扑物质表现出微妙的远程相干模式，无法通过局部描述来理解。由于这些全局效应，此类材料被认为特别适合强大的量子计算应用。因此，对这些物质的研究吸引了物理学、数学和计算机科学的研究人员。我们将探索这些材料、它们在自然界中的存在位置、它们的设计方法以及它们的应用。虽然我们的研究本质上主要是学术性的，但我们希望，类似于一个世纪前的基础半导体物理发现，我们的发现可能会促成未来的技术革命。