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Quasi-bound states in an NPN-type nanometer-scale graphene quantum dot under a magnetic field.

ABSTRACT: We solve the quasi-bound state-energy spectra and wavefunctions of an NPN-type graphene quantum dot under a perpendicular magnetic field. The evolution of the quasi-bound state spectra under the magnetic field is investigated using a Wentzel-Kramers-Brillouin approximation. In numerical calculations, we also show that the twofold energy degeneracy of the opposite angular momenta breaks under a weak magnetic field. As the magnetic field strengthens, this phenomenon produces an observable splitting of the energy spectrum. Our results demonstrate the relation between the quasi-bound state-energy spectrum in graphene quantum dots and magnetic field strength, which is relevant to recent measurements in scanning tunneling microscopy.

SUBMITTER: Pan Y

PROVIDER: S-EPMC7686324 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Quasi-bound states in an NPN-type nanometer-scale graphene quantum dot under a magnetic field.

Pan Yueting Y Ji Haijiao H Li Xin-Qi XQ Liu Haiwen H

Scientific reports 20201124 1

We solve the quasi-bound state-energy spectra and wavefunctions of an NPN-type graphene quantum dot under a perpendicular magnetic field. The evolution of the quasi-bound state spectra under the magnetic field is investigated using a Wentzel-Kramers-Brillouin approximation. In numerical calculations, we also show that the twofold energy degeneracy of the opposite angular momenta breaks under a weak magnetic field. As the magnetic field strengthens, this phenomenon produces an observable splittin ...[more]

PMID: 33235215

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