报告题目：Engineering the properties of graphene with adatoms and electric field
报 告 人：Jun Zhu，Department of Physics, Penn State University
报告摘要：Graphene is a fascinating 2D material from the viewpoint of both fundamental physics studies and applications. Its all-surface nature and intimate interactions with its environment present challenges as well as opportunities to engineer new properties. I will attempt to give a short update on the progress of the field in the last several years and discuss a few works in my lab in controlling existing and imparting new properties and functionalities in graphene and few-layer graphene systems. Functionalization of graphene using chemisorbed fluorine adatoms can profoundly modify its charge transport, leading to a band insulator. It also enhances the intrinsically weak spin-orbit coupling in pristine sheet and results in additional spin relaxation mechanisms that are tunable electrically. These new properties are potentially useful in spintronic applications. Bilayer and Trilayer graphene possess band gaps that are tunable via an electric field from zero to a few hundred meV, the exploitation of which could lead to optoelectronic devices.