1. Landau level properties of two prototypical bilayer graphenes 邱裕煌，何彥宏，林明發 成功大學 物理系
Introduction
Tight-binding Model
Results and Discussions
Conclusions
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2. hybridization of
atomic orbitals
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3. various dimensionality
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4. achievement of few-layered sheets
Mechanical exfoliation of highly oriented pyrolytic graphite Science 306, 666 (2004)
Epitaxial growth on silicon carbide Science 312,1191 (2006)
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5. stacking consequence AA
Simple hexagonal
stacking
Bernal stacking
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6. low-energy bands: monolayer & bilayer
Science 313, 951 (2007)
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7. angle-resolved photoelectron spectroscopy (ARPES)
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8. Landau quantization
2DEG
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9. experimental observation of Landau levels in graphene
1. Quantum Hall conductivity
2. Scanning tunneling spectroscopy
3. Magnetooptical transmission
(excitations between Landau levels)
Nature 438, 197 (2005)
Nat. Phys. 3, 623 (2007)
PRL 97, (2006)
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11. Tight-binding model Phys. Rev. 109, 272 (1958)
monolayer graphene γ0
bilayer Bernal graphene γ0 γ4 γ1 γ3 γ6
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12. zero-gap
semiconductor
semimetal

16. 12/33

17. Monolayer graphene

18. γ0
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19. 14/33

20. 15/33

21. Optical absorption function
Velocity matrix element
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24. Monolayer

25. AB-bilayer

26. AB-bilayer
Selection rules

27. 16/33

28. Selection rules

29. 17/33

30. Conclusions:
Two prototypes of bilayer graphenes, AA- and AB-stacking bilayer graphenes, exhibit different Landau level spectra, which reflect the fact that the magneto-electronic properties strongly depend on the stacking configurations.
The Landau wave functions of AA- and AB-stacking bilayer graphenes show dissimilar features and the dissimilarities are reflected in the magneto-optical absorption spectra, such as the distinct selection rules and different field-dependent absorption frequencies.
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31. Thanks for your attention!