石墨烯基磁量子环的低态能谱对磁场的依赖关系(英文)  

Magnetic-field dependence of low-lying spectra of graphene-based magnetic ring

作　　者：李泽民[1] 阮文英[2] 刘玉龙[1] 

机构地区：[1]中国科学院物理研究所,北京100190 [2]美国佐治亚理工学院物理学院

出　　处：《光散射学报》2012年第1期48-52,共5页The Journal of Light Scattering

基　　金：国家自然科学基金(10674171)

摘　　要：我们采用狄拉克-韦尔(Dirac-Weyl)模型,计算出二维石墨烯基磁量子环和磁量子点分别在垂直非均匀磁场下的低态能谱,并讨论包括两组旋量分量的低态能谱跟磁场的依赖关系。从直接对角计算法所获得的数值结果表明,在非均匀磁场下,磁量子点和磁量子环的能谱中的最低朗道能级(N-=0)皆为高度简并,且数值恒等为零。在其邻近较高的朗道能级,磁量子环出现了由磁场诱导的轨道角动量间的跃迁,而磁量子点则没有。最后本文指出,除了最低朗道能级(N-=0)外,两组旋量分量的能谱完全一样,只是其朗道能级所标记的两组量子数不同而已。Using the Dirac-Weyl model, we present the magnetic-field dependence of low-lying spectra of two-dimensional graphene-based magnetic dot and ring, including both spinor components, creating from perpendicular inhomogeneous magnetic fields. Numerical results obtained from direct diagonalization show that, under inhomogeneous magnetic fields, the lowest Landau level （ N^[-]= 0 ） is highly degenerate at zero energy, and for the other higher neighboring Landau levels, there exist angular momentum transitions in- duced by magnetic fields for the magnetic ring but not for the magnetic dot. Furthermore, the low-lying spectra for both spinor components, except for N-= 0, are exactly the same only with the states labeled by different sets of quantum numbers.

关 键 词：石墨烯 磁量子环 磁量子点 

分 类 号：O469[理学—凝聚态物理] O481.1[理学—电子物理学]