关键词: 石墨烯纳米带异质结/
自旋过滤效应/
自旋二极管效应/
巨磁阻效应
English Abstract
Magnetic device properties for a heterojunction based on functionalized armchair-edged graphene nanoribbons
Zhu Zhen,Li Chun-Xian,
Zhang Zhen-Hua
1.School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410114, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 61371065, 51302022) and Hunan Provincial Natural Science Foundation of China (Grant Nos. 12JJ3004, 14JJ2076, 2015JJ3002, 2015JJ2009, 2015JJ2013).Received Date:21 January 2016
Accepted Date:06 March 2016
Published Online:05 June 2016
Abstract:Graphene is predicted to hold a promising use for developing future miniaturized electronic devices. However, the magnetic transport properties based on the armchair-edged graphene nanoribbons (AGNRs) is less studied in currently existing work. So in this work the special chemical modified nanoribbons based on the edge of the AGNR bridged by the transition metal Mn atom and passivated subsequently by two F atoms or two H atoms (AGNR-Mn-F2 or AGNR-Mn-H2) are proposed theoretically. Our calculations from first-principle method based on the spin-polarized density functional theory combined with the non-equilibrium Green's function technique show that the heterojunction F2-AGNR-Mn-H2 consisting of such two types of nanoribbons possesses the excellent magnetic device features, namely, the spin polarization is able to reach almost 100% in a very large bias region, and under P magnetic configuration (the external magnetic fields applied perpendicularly to two electrodes are set to point to the same direction), the single spin filtering effects can be realized, while under the AP configuration (the external magnetic fields applied perpendicularly to two electrodes are set to point to the opposite directions), the dual spin filtering effects can be realized. It is also found that such a heterojunction features dual diode-like effect, and its rectification ratio is up to be 108. Additionally, changing the direction of switching magnetic field, namely, changing the magnetic configurations from one kind of case to another, would lead to an obvious spin valve effect, and the giant magnetoresistace approaches to 108%. These findings suggest that the excellent spin polarization, dual diode-like effect, and giant magnetoresistace effect can be realized simultaneously for this heterojunction, therefore, it holds good promise in developing spintronic devices.
Keywords: graphene nanoribbon heterojunction/
spin filter effect/
spin diode-like effect/
giant magnetoresistace effect
