石墨烯垂直结构量子输运性质的实验研究

Graphene - the ideal two-dimensional crystal consisting of single-layer carbon atoms - has many unique properties. Currently, a large number of studies have focused on graphene two-dimensional nature, while there are few studies about the quantum transport properties based on graphene vertical structure. Carrier transport in the vertical structure will be largely determined by the interfacial properties, which helps to reveal the interfacial properties of graphene with various types of materials. Furthermore, it is favorable to develop novel graphene devices, such as tunneling diodes with high switching ratio, and the ideal spin filter devices, which is complementary with the planar structure of graphene-based devices. This project intends to experiment on preparation of a variety of graphene based vertical structures and measure their quantum transport properties. The detailed study will focus on the physical properties of the vertical structures based on the ferromagnet/graphene/ferromagnet, supercondutor/graphene/superconductor, graphene/semiconductor/graphene, and graphene/insulating layer/graphene sandwiched systems. This project will allow us to reveal new physical phenomena and demonstrate potential applications based on graphene vertical structures.

石墨烯是由单层碳原子构成的理想二维晶体，它具有许多独特的性质。目前大量的研究都集中在石墨烯二维平面的性质，却鲜有关于石墨烯垂直结构的量子输运特性的报道。垂直结构中的载流子输运将很大程度上由界面性质所决定，这有助于揭示石墨烯与各类材料的界面性质。进一步由此开发一些新颖的石墨烯原型器件，例如：具有高开关比的隧穿二极管、接近理想状态的自旋过滤器件等，与目前各类基于石墨烯平面结构的器件形成互补。本项目拟从实验上制备各种石墨烯垂直结构并测量它们的量子输运特性，详细研究铁磁体/石墨烯/铁磁体、超导体/石墨烯/超导体、石墨烯/半导体/石墨烯、石墨烯/绝缘层/石墨烯等"三明治"垂直结构的物理性质，揭示新的物理现象和物理规律，展示具有潜在应用前景的器件效应。

石墨烯垂直结构中的载流子输运很大程度上由界面性质所决定，石墨烯可以与各类材料构成界面，从而有助于开发一些新颖的石墨烯功能器件。本项目主要研究了Au-石墨烯-Au“三明治”垂直结构的各向异性磁电阻效应；Co-石墨烯-Co“三明治”垂直结构的自旋阀器件；Pt-石墨烯-Pt“三明治”垂直结构的红外光电探测器；石墨烯-半导体异质结的光电响应特性；石墨烯-拓扑绝缘体异质结的量子输运特性；石墨烯-反铁磁绝缘体异质结的量子输运特性等。以通讯作者发表标注项目号的SCI论文36篇，包括3篇Nature Communications，1篇Nano Letters，9篇ACS Nano，2篇Small，8篇Nanoscale，1篇PRB，5篇APL等.