CAJ | 학술논문

利用第一性原理研究了两种具有边缘缺陷石墨烯纳米结的自旋输运,即边界氢原子饱和和未被饱和两种情况.结果表明:边缘缺陷改变了电子的输运行为.对于完整的石墨烯纳米带,两种自旋的电子在费米能级附近是完全简并的；对于含有边缘缺陷的石墨烯纳米结,两种自旋的电子在费米能级附近的很大能量范围内表现出自旋分离.电子局域态密度可进一步说明这种输运行为.这些纳米结可产生与自旋相关的极化电流.特别对于未饱和的缺陷结,在任何偏压下都有较高的自旋滤波效率.
이용제일성원리연구료량충구유변연결함석묵희납미결적자선수운,즉변계경원자포화화미피포화량충정황.결과표명:변연결함개변료전자적수운행위.대우완정적석묵희납미대,량충자선적전자재비미능급부근시완전간병적；대우함유변연결함적석묵희납미결,량충자선적전자재비미능급부근적흔대능량범위내표현출자선분리.전자국역태밀도가진일보설명저충수운행위.저사납미결가산생여자선상관적겁화전류.특별대우미포화적결함결,재임하편압하도유교고적자선려파효솔.
First-principles calculation was performed to investigate the transport properties of edge-defect junctions of graphene with H-terminated or bare edges,which were generated by removing edge carbon atoms from a perfect ribbon.The edge defect changes the electronic transport behavior of a zigzag graphene nanoribbon from spin-degenerated for a perfect ribbon to highly spin-polarized for edge-defective ones at the Fermi level.The electronic local density of states isosurface calculations could help understand the transport results.These junctions could generate spin-polatized currents.Especially,the bare edge-defect junction has a high spin filter efficiency regardless of the external bias.This behavior suggests a possible use of the edge-defective graphene in a spin filter system.