title: Planar Dirac electrons in magnetic quantum dots.
abstract: In this paper, we explore the size- and mass-dependent energy spectra and the electronic correlation of two- and three-electron graphene magnetic quantum dots. It is found that only the magnetic dots with large size can well confine the electrons. For large graphene magnetic dots with massless (ultra-relativity) electrons, the energy level structures of two Dirac electrons and even the ground state spin and angular momentum of three electrons are quite different from those of the usual semiconductor quantum dots. Also we reveal that such differences are not due to the magnetic confinement but originate from the character of the Coulomb interaction of two-component electronic wavefunctions in graphene. We reveal that the increase of the mass leads to both the crossover of the energy spectrum structures from the ultra-relativity to non-relativity ones and the increasing of the crystallization. The results are helpful for the understanding of the mass and size effects and may be useful in controlling the few-electron states in graphene-based nanodevices.
authors.affiliation: Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, People's Republic of China.
authors.forename: Ning
authors.initials: N
authors.lastname: Yang
authors.forename: Jia-Lin
authors.initials: JL
authors.lastname: Zhu
mesh_terms: D003198:Computer Simulation; D004579:Electron Transport; D006108:Graphite / Q000737:chemistry*; D060526:Magnetic Fields; D008956:Models, Chemical; D045663:Quantum Dots; D012666:Semiconductors; D055672:Static Electricity
chemical_list: D006108:Graphite