Structural, electronic and magnetic properties of manganese doping in the upper layer of bilayer graphene

Abstract

First-principles spin-polarized calculations have been conducted to investigate the structural, electronic and magnetic properties of 3d transition metal Mn doping into two typical sites in the upper layer of bilayer graphene with the AB Bernal structure. One of the doping sites is above the center of a carbon hexagon of the lower graphene layer (called the H site) and the other is directly on top of a carbon atom of the lower graphene layer (called the T site). We found that Mn doping enlarges the interlayer distance in bilayer graphene. Charge density distribution indicates that the region between the upper and lower graphene layer has apparent covalent-bonding characters due to the Mn doping. In the spin-polarized band structure of H site doping, the π and π(*) bands separate from each other at the Dirac point both in majority spin and minority spin. In the band structure of T site doping, the Fermi level is located above the Dirac point and moves to the conduction bands in majority spin and minority spin, making the bilayer graphene n doped. A high spin polarization of 95% is achieved due to the H site doping. The local moment of Mn for H and T site doping is reduced to 1.76 μ(B) and 1.88 μ(B), respectively, which are smaller than the value (5 μ(B)) in the free state.

Physicochemical Characterization, and Relaxometry Studies of Micro-Graphite Oxide, Graphene Nanoplatelets, and Nanoribbons

“…These values fall outside the range of values for obtained for various paramagnetic complexes, which are between 1 and 6._ENREF_35 However, q values as high as high as 20 have reported for gadofullerenes [9]. Theoretical studies on Manganese intercalation within graphene suggest coordination of manganese to the graphene sheets with 1–3 co-ordination bonds [38]. Assuming most of the intercalated graphene is Mn 2+ in the high spin state, the co-ordination number can be between 4 and 8 and thus, the possible co-ordination sites for water molecules will be between 1 and 7, and value obtained from the NMRD fits is close to this value.…”

Morphology and flexibility of graphene and few-layer graphene on various substrates

“…For example, single layer graphene deposited on a boron nitride surface could develop an energy gap [14]. Using a manganese doped substrate for bilayer graphene preparation should also lead to a gap and even to a highly spin polarized state [15], which would be ground-breaking for * Electronic address: Ulrich.Stoeberl@physik.uni-r.de † present address: Department of Physics, University of Hamburg spintronics in carbon-based devices.…”

“…For example, single layer graphene deposited on a boron nitride surface could develop an energy gap [14]. Using a manganese doped substrate for bilayer graphene preparation should also lead to a gap and even to a highly spin polarized state [15], which would be ground-breaking for * Electronic address: Ulrich.Stoeberl@physik.uni-r.de † present address: Department of Physics, University of Hamburg spintronics in carbon-based devices.In this letter we report our experimental studies on the influence of different kinds of substrates on the morphology of graphene and few layer graphene using scanning electron microscopy (SEM) and atomic force microscopy (AFM). We investigate the polar (001) semiinsulating GaAs surface (I), Mn-doped (001) GaAs (II), In 0.75 Ga 0.25 As (III), and 300nm SiO 2 (IV) as a reference.…”

Magnetic Properties of Mn Doped Armchair Graphene Nanoribbon

“…13) Theoretical calculations on doped graphene and bilayer graphene with TM and Mn have been also reported. 14,15) In this work we investigate the magnetization and electronic structure of Mn doped armchair ribbon N ¼ 8 with various doping densities by first-principles density functional calculations. The effect of doping on the edge of the nanoribbon and the stability of the doped structures will be discussed.…”