Quantum dynamics of electrons in emerging van der Waals devices

点击翻译按钮获取中文摘要

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.