St.-Petersburg State University, Ulyanovskaya 1, Petrodvoretz, St.-Petersburg 198504, Russia.
Nanotechnology. 2013 Jul 26;24(29):295201. doi: 10.1088/0957-4484/24/29/295201. Epub 2013 Jun 25.
A modification of the contact of graphene with ferromagnetic electrodes in a model of the graphene spin filter allowing restoration of the graphene electronic structure is proposed. It is suggested for this aim to intercalate into the interface between the graphene and the ferromagnetic (Ni or Co) electrode a Au monolayer to block the strong interaction between the graphene and Ni (Co) and, thus, prevent destruction of the graphene electronic structure which evolves in direct contact of graphene with Ni (Co). It is also suggested to insert an additional buffer graphene monolayer with the size limited by that of the electrode between the main graphene sheet providing spin current transport and the Au/Ni electrode injecting the spin current. This will prevent the spin transport properties of graphene from influencing contact phenomena and eliminate pinning of the graphene electronic structure relative to the Fermi level of the metal, thus ensuring efficient outflow of injected electrons into the graphene. The role of the spin structure of the graphene/Au/Ni interface with enhanced spin-orbit splitting of graphene π states is also discussed, and its use is proposed for additional spin selection in the process of the electron excitation.
提出了一种改进的石墨烯与铁磁电极接触的方法,该方法应用于石墨烯自旋滤波器模型中,可恢复石墨烯的电子结构。建议在石墨烯和铁磁(Ni 或 Co)电极之间的界面插入单层 Au,以阻止石墨烯与 Ni(Co)之间的强相互作用,从而防止石墨烯电子结构在与 Ni(Co)直接接触时发生破坏。还建议在主石墨烯片和注入自旋电流的 Au/Ni 电极之间插入一个具有电极尺寸限制的额外缓冲石墨烯单层,以提供自旋电流传输。这将防止石墨烯的自旋输运性质影响接触现象,并消除石墨烯电子结构相对于金属费米能级的钉扎,从而确保注入电子有效地流入石墨烯。还讨论了增强石墨烯 π 态自旋轨道劈裂的石墨烯/Au/Ni 界面的自旋结构的作用,并建议在电子激发过程中用于进一步的自旋选择。