Twistronics based on 2D materials and related van der Waals structures
Twisted van der Waals heterostructures (TVDHs) are two-dimensional materials composed of two or more layers of different two-dimensional materials, such as graphene, transition metal dichalcogenides, hexagonal boron nitride, and black phosphorus, which are stacked together with a relative twist angle. TVDHs have attracted considerable attention due to their unique electronic properties, which are determined by the interlayer interaction and the twist angle. These properties include anisotropic Dirac cones, superconductivity, and valley-polarized photocurrents. TVDHs have potential applications in optoelectronics, valleytronics, spintronics, and quantum computing.
Two-dimensional materials such as Moiré superlattices are a new class of materials with exciting properties that can be used in a variety of applications. The Moiré superlattice is a periodic structure formed by the overlap of two layers of two-dimensional materials, such as graphene, hexagonal boron nitride, transition metal dichalcogenides, and others. By carefully controlling the twist angle between the two layers, the Moiré superlattice can be tuned to host a variety of electronic and optical properties, such as flat bands, highly localized states, and valley-selective optical transitions. These properties make Moiré superlattices attractive for applications in optoelectronics, spintronics, and quantum computing.
Van der Waals heterostructures are two-dimensional materials composed of two or more layers of different materials, such as graphene and hexagonal boron nitride, that are held together by weak van der Waals forces. These forces are much weaker than the covalent bonds that hold atoms together in a single material, but they are still strong enough to keep the layers together. Van der Waals heterostructures have unique electronic, optical, and mechanical properties that make them attractive for a variety of applications, such as optoelectronics, catalysis, and sensors. They are also being explored for use in energy storage and conversion, as well as for use in quantum computing.
Photodetectors are the foundation of modern information technology. They are intermediaries for converting optical signals into electrical signals and play an essential role in the field of sensors. They are also irreplaceable in various areas of the national economy and military. Currently, research hotspots for photodetectors are mainly two-dimensional material photodetectors, which possess distinct physical properties due to their small size, high surface energy, large proportion of surface atoms, and large specific surface area. These include surface effects, quantum size effects, and macroscopic quantum tunneling effects. Compared to photodetectors based on bulk materials and thin film materials, two-dimensional photodetectors have the advantages of miniaturization, enhanced light energy absorption, and higher carrier mobility, which leads to a faster response time.
The research goal of this project is to explore the applications of photodetectors based on 2D materials, to explore the interaction mechanism between electrons, photons and phonons, and to promote the commercialization of nanophotonic devices. This project will help to gain a deeper understanding of the photoelectric conversion mechanism of new materials, the electron-photon-phonon micro-mechanism and relaxation mechanism, obtain first-hand experimental data, and lay a foundation for the application of nano-optical quantum devices, thus promoting the development and innovation of nano-optoelectronics.
The key to researching photodetectors based on 2D materials is to identify various ways and means to overcome the existing experimental conditions and materials to regulate the photocurrent, broaden the parameters of transmission and regulation of new optoelectronic devices, so as to uncover more novel quantum transport phenomena and military and defense applications for optoelectronic devices.
