层状钴氧化物Bi2Sr2Co2O8纳米结构的二维输运特性研究

Since the discovery of graphene and related two-dimensional systems that exhibit many novel and special properties, study on two-dimensional layered materials has become a scientific hot topic recently. Due to the wide prospects in semiconductor devices, clean energy, and biomedicine, in-depth investigations on various two-dimensional systems are highly important. In this project, we plan to prepare nanosheets of the layered cobalt oxide Bi2Sr2Co2O8 with different thickness including one or a few atomic layers by mechanical exfoliation, and focus on their transport characteristics in the two-dimensional scale as well as determine their electronic band structure. From this study, we can establish the physical scenario of the transport behavior, understand the correlations between the in-layer and out-of-layer interactions, microstructure and transport characteristics, deepen the understanding of the particular transport properties in low-dimensional systems. This project can provide some new information for the study of electron strongly correlated systems and low-dimensional physical phenomena, and provide theoretical support for designing new low-dimensional quantum devices with special performance.

由于石墨烯等二维体系表现出许多新奇而独特的性质，近年来二维层状材料已成为科学研究的热点。由于二维材料在半导体器件、绿色能源、生物医学等方面具有广泛的应用前景，深入研究多种二维体系的性质具有重要的意义。本项目拟利用机械剥离的方法制备不同厚度的仅包含一个或几个原子层的层状钴氧化物Bi2Sr2Co2O8纳米片，系统研究该层状体系在二维尺度下的输运特性，并确定二维Bi2Sr2Co2O8的能带结构。通过这些研究，建立起其输运行为的物理图像，理解该二维层状材料的层内层间耦合作用、微结构与输运特性之间的关联，加深对低维体系独特的输运性质的认识。本项目可以为当前电子强关联系统和低维物理现象的研究提供新的信息，并为设计具有独特性能的低维量子器件提供物理依据。

由于石墨烯等二维体系表现出许多新奇而独特的性质，近年来二维层状材料已成为科学研究的热点。由于二维材料在半导体器件、绿色能源、生物医学等方面具有广泛的应用前景，深入研究多种二维体系的性质具有重要的意义。我们利用机械剥离的方法制备了不同厚度的仅包含一个或几个原子层的层状钴氧化物Bi2Sr2Co2O8纳米片，系统研究该层状体系在二维尺度下的输运特性，发现了其层数依赖的金属-半导体转变现象并深入研究了其物理机制起源。通过这些研究，建立起了其输运行为的物理图像，理解了该二维层状材料的层内层间耦合作用、微结构与输运特性之间的关联，加深对低维体系独特的输运性质的认识。同时，我们也关注了层状二维材料MoS2和WSe2纳米片中独特的发光性质与磁性质，系统研究了室温下MoS2纳米片缺陷对其发光的影响，以及WSe2纳米片中的铁磁性的起源。这些研究可以为当前电子强关联系统和低维物理现象的研究提供新的信息，并为设计具有独特性能的低维量子器件提供物理依据。