题 目：Polarization-enabled electronic properties of hybrid 2D-ferroelectric structures
主讲人：Alexei Gruverman 教授、博士生导师
美国内布拉斯加大学，林肯
主持人：周益春 教授
伟德BETVLCTOR1946校长
时 间：2018年5月8日(星期二)上午10:30
地 点：材料科学与工程学院学术报告厅 二教319
内容简介：
In recent years, there has been an unprecedented interest in various two-dimensional (2D) materials that often possess unique physical and chemical properties that cannot be found in their three-dimensional counterparts. An important advantage of 2D materials is the fact that due to their planar morphology they can be easily integrated with other 2D materials and functional films, resulting in multilayered structures with new properties. In particular, there was a considerable interest in a novel type of electronic devices, in which graphene, a 2D carbon material, was coupled with different ferroelectric (FE) materials. Electrically switchable ferroelectric polarization opens a possibility of electrical control of the functional properties of the adjacent graphene layer.
In this presentation, I will discuss implementation of the hybrid electronic devices comprising 2D materials and FE thin films (2D-FE) that exhibit polarization-controlled non-volatile modulation of the electronic transport. While many 2D materials can be considered in conjunction with FE materials, this talk primarily focuses on the use of graphene and transition metal dichalcogenide MoS2. Specifically, it will be shown how polarization reversal can modulate (1) the in-plane transport of the interfacial conducting channel in the FE field effect devices, and (2) the perpendicular-to-plane tunneling conductance in the FE tunnel junction devices. I will demonstrate that interface engineering is a critical component determining the functional properties of these devices. A simple phenomenological modeling is developed to predict how the interface chemistry affects the electronic and transport properties of the 2D-FE structures.
