张淑华,柳福提,程晓洪
Zhang Shuhua,Liu Futi,Cheng Xiaohong

• 1:宜宾学院化学与化工学院
• 2:宜宾学院物理与电子工程学院

摘要(Abstract)：

基于密度泛函理论,运用非平衡格林函数对(GaAs)_4原子链耦合石墨烯纳米条带的电子输运性质进行了第一性原理计算,结果发现通过改变原子链与石墨烯之间的距离可以有效调制系统的电子传输行为.当(GaAs)_4原子链与石墨烯之间的距离d在0.10~0.28nm的范围内变化时,石墨烯、原子链上各自的电子传输要相互影响,且系统的平衡电导在2G_0~7G_0之间发生G_0(G_0=2e~2/h)整数倍的变化,即表现出量子化电导现象;当d>0.28nm时,总的电导等于各自的电导之和,此时(GaAs)_4原子链与石墨烯之间的耦合很弱,各自的电子输运相互影响很小.
The electron transport properties of(GaAs)_4 atomic chain coupling graphene ribbon was calculated using density functional theory and non-equilibrium green's function from the first principles.The results showed that changing the distance of atomic chain with the graphene can modulate electron transport properties of system.As the distance changed in the range of 0.10-0.28 nm,electrons transported in graphene and atomic chain have an influence on each other.The equilibrium conductance of(GaAs)_4 atomic chain coupled with graphene ribbon changed from 2 G_0 to 7 G_0.The results showed that there was phenomenon of quantized conductance.When d>0.28 nm,the coupling effect of atomic chain and the graphene is weak,electrons transported in graphene and atomic chain have a small influence on each other.The total conductance of system is equal to the sum of their respective conductance at this time.

关键词(KeyWords)： GaAs原子链;石墨烯;电子输运;非平衡格林函数
GaAs atomic chain;graphene;electron transport;non-equilibrium Green function

Abstract:

Keywords:

基金项目(Foundation): 四川省高等学校重点实验室开放课题基金(JSWL2015KF02);; 宜宾市重点科技项目(2015SF02);; 宜宾学院重点科研项目(2015QD14)

作者(Author): 张淑华,柳福提,程晓洪
Zhang Shuhua,Liu Futi,Cheng Xiaohong

DOI: 10.16366/j.cnki.1000-2367.2018.02.006

参考文献(References)：

• [1]Novoselov K S,Geim A K,Morozov S V,et al.Electric field effect in atomically thin carbon films[J].Science,2004,306(5696):666-669.
• [2]Neto A H C,Guinea F,Peres N M R,et al.The electronic properties of graphene[J].Reviews of Modern Physics,2009,81(1):109
• [3]BREY L,FERTIG H A.Electronic states of graphene nanoribbons studied with the Dirac equation[J].Phys Rev B,2006,73(23):235411.
• [4]Novoselov K S,Geim A K,Morozov S V,et al.Two-dimensional gas of massless Dirac fermions in graphene[J].Nature,2005,438(7065):197-200.
• [5]Zhang Y B,Tan Y W,Stormer H L,et al.Experimental observation of the quantum hall effect and berry’s phase in graphene[J].Nature,2005,438(7065):201-204.
• [6]Nakada K,Fujita M,Esselhaus dr G,et al.Edge state in graphene ribbons:nanometer size effect and edge shape dependence[J].Phys Rev B,1996,54(24):17954.
• [7]Zhang H X,Wang Z F,Luo T,et al.Analytical study of electronic structure in armchair graphene nanoribbons[J].Phys Rev B,2007,75(16):165414.
• [8]Pisani L,Chan J A,Montanari B,et al.Electronic structure and magnetic properties of graphitic ribbons[J].Physical Review B,2007,75(6):064418.
• [9]Oswald W,Wu Z.Energy gaps in graphene nanomeshes[J].Physical Review B,2012,85(11):115431.
• [10]Kan E,Li Z,Yang J,et al.Half-metallicity in edge-modified zigzag graphene nanoribbons[J].Journal of the American Chemical Society,2008,130(13):4224-4225.
• [11]Lin X,Ni J.Half-metallicity in graphene nanoribbons with topological line defects[J].Physical Review B,2011,84(7):075461.
• [12]Tian W,Zeng Y C,Zhang Z H.Electronic properties of graphene nanoribbons with periodically hexagonal nanoholes[J].Journal of Applied Physics,2013,114(7):074307.
• [13]曾永昌,田文,张振华.周期性纳米洞内边缘氧饱和石墨烯纳米带的电子特性[J].物理学报,2013,62(23):236102.
• [14]An Y,Zhang M,Wu D,et al.The magnetism and spin-dependent electronic transport properties of boron nitride atomic chains[J].The Journal of chemical physics,2016,145(4):044301
• [15]An Y,Wang K,Yang Z,et al.Negative differential resistance and rectification effects in step-like graphene nanoribbons[J].Organic Electronics,2015,17:262-269
• [16]Kwapinski T.Phase-dependent electron transport through a quantum wire on a surface[J].J Phys:Condensed Matter,2012,24(5):055302.
• [17]Li H D,Zheng Y S.Contact conductance between graphene and quantum wires[J].Phys Lett A,2009,373(5):575-582.
• [18]Yang F B,Cheng Y,Liu F T,et al.Spin-dependent transport through a quantum wire on a graphene surface[J].Appl Phys Lett,2013,102(1):011911.
• [19]Yang F B,Cheng Y,Liu F T,et al.Spin-dependent fano resonance in an impurity-doped graphene coupled to ferromagnetic leads[J].Appl Phys Lett,2013,103(3):033513.
• [20]张淑华,程晓洪,柳福提.原子链耦合石墨烯电子输运性质的第一性原理计算[J].河北师范大学学报(自然科学版),2017,41(1):32-38.
• [21]柳福提,张淑华,程艳,等.(GaAs)n(n=1-4)原子链电子输运性质的理论计算[J].物理学报,2016,65(10):106201.
• [22]Büttiker M,Imry Y,Landauer R,et al.Generalized many-channel conductance formula with application to small rings[J].Physical Review B,1985,31(10):6207.
• [23]Brandbyge M,Mozos J L,Ordejón P,et al.Density-functional method for nonequilibrium electron transport[J].Physical Review B,2002,65(16):165401.
• [24]Rocha A R,García-Suárez V M,Bailey S,et al.Spin and molecular electronics in atomically generated orbital landscapes[J].Physical Review B,2006,73(8):085414.
• [25]Perdew J P,Zunger A.Self-interaction correction to density-functional approximations for many-electron systems[J].Physical Review B,1981,23(10):5048.
• [26]Troullier N,Martins J L.Efficient pseudopotentials for plane-wave calculations[J].Physical Review B,1991,43(3):1993.
• [27]Dai Z X,Zheng X H,Shi X Q,et al.Effects of contact geometry on transport properties of a Si4cluster[J].Physical Review B,2005,72(20):205408.
• [28]Liu F T,Cheng Y,Yang F B,et al.Effects of contact geometry on the transport properties of a silicon atom[J].Chinese Physics Letters,2013,30(10):107303.