• 文献标题:   Modulation effects on Landau levels in a monolayer graphene
  • 文献类型:   Article
  • 作  者:   HO JH, LAI YH, CHIU YH, LIN MF
  • 作者关键词:  
  • 出版物名称:   NANOTECHNOLOGY
  • ISSN:   0957-4484 EI 1361-6528
  • 通讯作者地址:   Natl Cheng Kung Univ
  • 被引频次:   19
  • DOI:   10.1088/0957-4484/19/03/035712
  • 出版年:   2008

▎ 摘  要

Magnetoelectronic properties of a single-layer graphene are studied by the Peierls tight-binding model. A new numerical technique is developed to obtain a band-like Hamiltonian matrix. A spatially modulated magnetic field B' could drastically alter the Landau levels due to a uniform magnetic field B. The modulation effects include enhancement in dimensionality, change of energy dispersions, destruction of state degeneracy and creation of band-edge states. The dispersionless Landau levels, those at the Fermi levels excepted, become the 1D parabolic bands. The density of states thus exhibits many pairs of asymmetric prominent peaks. The height, frequency and number of pronounced peaks strongly depend on the modulation strength. These characteristics are hardly affected by the period and direction when B' is much weaker than B. The predicted results could be verified by experimental measurements on magneto-optical absorption spectra.