title: Chemically functionalized germanene for spintronic devices: a first-principles study.
abstract: We have carried out first-principles calculations to explore various chemically functionalized germanene nanomaterials as two-dimensional spintronic devices. The germanene functionalized with O on one side and H on the other side is a ferromagnetic metal, and the phenomenon of negative differential conductance is observed. Moreover, we construct a spin-filter device from it, and about 15% spin filter efficiency is achieved in its ground state by using finite bias. The germanene semi-functionalized with a methyl (-CH3) group is a ferromagnetic semiconductor with a small direct bandgap, and it has highly spin-polarized electronic and transport properties. We proposed that a spin-valve nanodevice with a giant magnetoresistance of up to 10(7)% can be obtained from the semi-methylated germanene nanostructure by introducing an achievable magnetic field to stabilize its metal-like ferromagnetic state. Our findings could be helpful for practical applications of two-dimensional germanane-based nanomaterials in spintronic devices in the future.
authors.affiliation: School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China and School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, Hubei, China. zenghui@yangtzeu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
authors.affiliation: School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China and School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou 434023, Hubei, China. zenghui@yangtzeu.edu.cn and School of Physics, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zeng