锯齿型石墨烯纳米带结的自旋输运性质

Spin Transport Properties of Zigzag Graphene Nanoribbon Junctions

用第一性原理密度泛函理论和非平衡格林函数理论,研究上下两层石墨烯的交叠面积对于断裂的锯齿型石墨烯纳米带结自旋输运性质的影响。结果表明:吸附石墨烯纳米片后体系呈现半导体输运特性,自旋向上和自旋向下的电流呈非简并,且随着交叠碳原子链的减少,自旋输运性质变弱。但是,在边缘吸附时,由于自旋向上和自旋向下的HOMO+1、HOMO和LUMO均具有非常好的扩展性,体系的自旋输运性质最好。此研究为制备石墨烯电路及器件提供理论参考。

With density functional theory and nonequilibrium Green’s functional method,we studied effects of overlap area on spin transport properties of zigzag graphene nanoribbon(ZGNR)junctions.It shows that the system exhibits semiconductor transport properties.The spin up and spin down currents are nondegenerate after adsorption of graphene nanosheets.With the decrease of overlapping carbon atom chains,the transport ability is decreased.However,as graphene nanosheets are adsorbed on the edges of ZGNR spin transport properties of the system are the best,due to the excellent expansibility of spin up and spin down of Homo+1,Homo and LUMO.It provides a theoretical reference for the preparation of graphene circuits and devices.