Research Of Electronic Structures And Dielectric Properties Of Doped Multilayer Graphene

The ground-breaking experiments of graphene were awarded the2010Nobel Prize ofPhysics[7][8][9][10]. The reasons for the winning of graphene should be the following twoaspects: First, the adventure of graphene would bring a resolution of electronic industrydevelopment and maybe take humanity material progress into another era.Second, the graphene’scoming into reality will supply an appotunity to test or verify the modern quantum field theory,especially the QED.The present work focuses on the application of graphene.From an ab-initial calculation basedon density functional theory, we abtain the energy bands and the dielectric properties of dopedgraphene multilayer within LDA approximation of the exchange-correlation energy and projectoraugmented wave (PAW). The topic is carried out because of the giant semi-conductiveapplication potential of grapheme. Many experimental and theoretical works have reported thatenergy gap value of graphene bilayer can be tuned from0.1eV to0.3eV while experiencing avertical electric field to the plane. And ABC graphene trilayer can be semi-conductive byexcerting external field or external atomic doping.Especially, many experimental and theoreticalresults indicates doping in graphene system can obtain energy gaps. Combine with moderndeveloped semiconductor engineering, it can be concluded that doping is a straightforward andfeasible method for altering properties of materials. Taking much experience and references intoour calculation, we find the zero gap of graphene bilayer is opened to0.3eV by transitionmental atom Ni doping on top site of graphene interlayer while the doping trilayer structures staythe metal features. In doped bilayer structures, Ni atom concentration change is considered toresearch the bands alternation. The static dielectric tensors of two doping bilayer structures withband gap near Fermi energy are caltulated respectively. Some results (such as engey bandgraphs, band gap values or lattice constant) abtained are compared with recently credibleexpremental data or theoretical analysis. Some results and methods are quoted at some sectionsof the work. At the end of the work, a relation of various branches in theoretical physics thatreferes to graphene is briefly introduced for the purpose of promoting the investigation interest inthe field of graphene electronics and stimulating inspiration of further theoretical researches.A lot of works referring to graphene are worthy noting no matter domestic or abroad,experimental or theoretical. A first principle study of energy bands structure of doped multilayergraphene belongs to theoretical analysis framework. So there maybe not exist correspondence inexperimental data. We hope some results such as relative permittivity or gap values can give asimple instruction to experimental works in the field of graphene electronics.