我們主要利用緊束模型(Tight-binding Model)來計算二維石墨層的磁電結構, 而我們發現磁電結構會隨著磁場的變化而有明顯的改變,這是由於磁場對布洛赫方程式(Bloch function)在真實空間與K空間造成週期性邊界條件而產生,因此,不同的磁場下,石墨層能帶的形狀,分佈,與藍道能階的振蕩週期也不同.這些能帶的特性同時也反應在態密度(DOS)聯合態密度(JDOS)與吸收譜上.例如可以在態密度(DOS)中找到許多呈現dleta-funtion形式或是開根號形成的發散,以及在吸收譜中,隨磁場變化而有不同結構的產生.

　　Magnetoelectronic structures of a two-dimensional (2D) graphite sheet are calculated by the tight-binding model.They are very sensitive to the magnitude of Perpendicular magnetic field (B).B imposes the periodical boundary condition on the Bloch functions in the real and momentum spaces. Thus,B changes energy dispersions, energy spacing, bandwidth, and oscillation period of Landau levels. B could reduce the dimensionality of a graphite sheet.Energy dispersions mainly exhibit zero-dimensional(or 1D) characteristics. A lot of delta-function-like peaks (or square-root peaks) in the density of states can be clearly found.The magnetic field dramatically changes the joint density of states and the magnetoabsorption spectra. So, many peaks with different structures are produced.

1. Introduction　　　　　　　　　　　　　　　　　　　　1
2. Tight-binding Method　　　　　　　　　　　　　　　　2
3. The Magnetoelectronic Properties　　　　　　　　　　 　 7
4. Conclusions　　　　　　　　　　　　　　　　　　　　 15
5. Reference　　　　　　　　　　　　　　　　　　　　　15
6.Appendixes:programs　　　　　　　　　　　　　　　　20

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