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arXiv · 0709.1803

Electron energy spectrum and the Berry phase in graphite bilayer

G. P. Mikitik·Yu. V. Sharlai
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Abstract

We emphasize that there exist four Dirac-type points in the electron-energy spectrum of a graphite bilayer near the point K of its Brillouin zone. One of the Dirac points is at the point K, and three Dirac points lie nearby. Each of these three points generates the Berry phase $π$, while the Dirac point at K gives the phase $-π$. It is these four points that determine the Berry phase in the bilayer. If an electron orbit surrounds all these points, the Berry phase is equal to $2π$.

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G. P. Mikitik, Yu. V. Sharlai. 2007-12-18. Electron energy spectrum and the Berry phase in graphite bilayer. https://doi.org/10.1103/physrevb.77.113407

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