Quantum dynamics of electrons in emerging van der Waals devices

数百种不同类型的原子级薄二维（2D）材料的丰富多样的特性为基础科学和技术应用提供了令人兴奋的新研究方向。当不同的层堆叠在一起时，这些2D晶体的特征通常会被保留甚至增强。这些二维晶体堆是一类新的“设计师”材料，称为货车德瓦尔斯（vdW）异质结构，它提供了一种方法来调整和利用二维材料中电子的新颖和奇异的量子特性。通过选择适当的层材料组合，电子传输特性可以内置并针对特定的器件应用进行定制。此外，它们的电子特性可以通过改变器件层之间的相对扭转角来微调。这为新科学和应用的发展提供了材料选择和相对扭曲角的巨大配置空间：最近展示的现象包括晶体管，发光二极管，灵敏的光电探测器，自旋阀，超导性，磁邻近效应，介电屏蔽效应和激光。该项目的目标是了解vdW异质结构中电子量子动力学的基本物理学，并利用这一见解来研究控制电子动力学的新方法，以用于未来的器件应用。我们的工作将集中在vdW异质结构的电子特性的新的理论模型的发展，调查：由于晶格振动在vdW异质结构的面内传输和载流子迁移率的限制;强磁场和层图案化对电子动力学的影响;层间隧道通过量子限制的子带在vdW半导体。这些理论的成功发展将与学术和工业研究人员高度相关。它们将用于设计新的高频晶体管和振荡器，应用于多值逻辑器件、通信、安全、医学和成像。我们将与曼彻斯特大学和诺丁汉大学的理论和实验同事以及日本大坂大学的理论家密切合作，并与工业界建立新的联系。总之，这些合作将允许直接反馈测量到我们的理论工作方案和从我们的理论工作方案，从而使双方的理论和实验工作的快速发展。

The rich and diverse properties of the several hundred different types of atomically thin, two dimensional (2D) materials offer exciting new research directions for both fundamental science and for technological applications. The character of these 2D crystals are often preserved and even enhanced when different layers are stacked together. These 2D crystal stacks are a new class of "designer" materials known as van der Waals (vdW) heterostructures which offer a way to tune and exploit the novel and exotic quantum properties of electrons in 2D materials. By choosing the appropriate combination of layer materials, electron transport characteristics can be built-in and tailored for specific device applications. Moreover, their electronic properties can be fine-tuned by modifying the relative twist angle between the layers of the devices. This provides a huge configuration space of material choice and relative twist angle for the development of new science and applications: recently demonstrated phenomena include transistors, light emitting diodes, sensitive photodetectors, spin valves, superconductivity, magnetic proximity effects, dielectric screening effects and lasing. The goal of this project is to understand the fundamental physics of electron quantum dynamics in vdW heterostructures and use this insight to investigate new ways to control electron dynamics for future device applications. Our work will focus on the development of new theoretical models of the electronic properties of vdW heterostructures to investigate: the limits to in-plane transport and carrier mobility due to lattice vibrations in vdW heterostructures; the effect of strong magnetic fields and layer patterning on the electron dynamics; interlayer tunnelling through quantum-confined sub-bands in vdW semiconductors. The successful development of these theories will be highly relevant to both academic and industrial researchers. They will be used to design new high-frequency transistors and oscillators with application in multi-valued logic devices, communication, security, medicine, and imaging. We will work closely with theoretical and experimental colleagues at the Universities of Manchester and Nottingham, with theorists at Osaka University, Japan, and develop new links with industry. Together, these collaborations will allow direct feedback of measurements into and from our programme of theoretical work and thus enable mutual fast development of both the theroetical and experimental work.