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Abstract: The low-energy Landau levels of multilayer graphene ribbons with AB-stacking in the presence of a uniform perpendicular magnetic field (B) are investigated by the Peierls coupling tight-binding model. They are dominated by the B-field strength, the interlayer interactions, and the ribbon width. Many dispersionless Landau levels and parabolic energy bands exist along k x and k z directions respectively. The former are doubly degenerate, while state degeneracy is absent for the latter. The occupied valence bands are asymmetric to the unoccupied conduction bands about the Fermi level (E F). Such features are directly reflected in density of states (DOS). DOS exhibits a lot of asymmetric prominent peaks because of 1D curving bands. Meanwhile, the Landau-level energies following the simple relation are observed. The predicted magnetoelectronic properties could be examined by the experimental measurements on transport conductance and absorption spectra. [Copyright &y& Elsevier]

Abstract: Magnetic bands of the hydrogen-terminated monolayer zigzag graphene ribbon subject to the spatially inhomogeneous magnetic field () are investigated through the Peierls-coupling tight-binding model. is a constant magnetic field defined on a strip of finite width that is smaller than the ribbon width. , step-function-like magnetic field, can change band shapes, alter band curvature, shift band edge states, and hybridize parabolic bands, sublinear bands, partial Landau levels, and Hall edge states. Such a not only induces Landau levels in the magnetic field but also modifies the parabolic bands along the boundary between the magnetic and nonmagnetic areas. The magnetic bands are strongly dependent on the configuration of the spatially inhomogeneous magnetic field. Density of states, e.g., the position, height and number of dominant strong peaks, feature such interesting characteristics. [Copyright &y& Elsevier]

Abstract: The tight-binding model is employed to study magnetoelectronic structures of the AB-stacked graphite. A specifically full band calculation on overall energy region is presented to compare with SWMcC method, which only concerns the magnetoelectronic structures along the HKH-axis. It is found that magnetoband structures, strongly depending on the perpendicular magnetic field (B) and the interlayer interactions, exhibit 0D, 1D and 2D characteristics at the strong magnetic field. The physical origin of 0D, 1D and 2D Landau levels is intensely discussed to show its speciality for graphite. Pronounced structures, including sharp peaks, square-root peaks, and logarithmic divergences, can be clearly found in the density of states (DOS). And the energy dispersions and DOS are specially sensitive to the magnitude of B: the lower the magnetic field is, the more Landau levels exist nearby Fermi energy (E F). Meanwhile, the interlayer interactions significantly affect the state energies and the DOS features, e.g., peak position and peak shape. DOS in the form of sharp peak (square-root peaks) below (above) E F is expected to play an important role in such physical properties as absorption spectra. [Copyright &y& Elsevier]

Abstract: Magnetoelectronic structures of the AA- and AB-stacked nanographite ribbons, which strongly depend on magnitude and direction of magnetic field, ribbon edges, and interribbon interactions, are studied within the frame of tight-binding model. First, the origins of Landau subbands and additional spectra, induced by the perpendicular magnetic field , chiefly changing the intraribbon interaction, are analytically studied in the zigzag systems. This method allows us to intuitively understand the magnetoband structures of the finite size systems. Then, the interribbon interactions modify Landau subbands and change energy dispersions, energy spacing, bandwidth and oscillation period of Landau subbands. On the other hand, the parallel magnetic field changes the interribbon interactions and leads to the Landau levels along . Furthermore, can induce the metal–insulator transition in the AB-stacked armchair ribbons. Above all, magnetic field and interribbon interactions vitalize the magnetoband structures. So, there are rich structures in density of states: sharp peaks, square-root peaks, logarithmic divergences and oscillating structures. Finally, DOS can clearly exhibit 0D, 1D and 2D characteristics. And this specific is expected to have great effects on the physical properties, e.g. optical, magnetic and transport properties, of the stacked ribbons. [Copyright &y& Elsevier]