Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Trigonal warping and Berry’s phase Npi in ABC-stacked multilayer graphene.
AU - Koshino, Mikito
AU - McCann, Edward
PY - 2009/10/15
Y1 - 2009/10/15
N2 - The electronic band structure of ABC-stacked multilayer graphene is studied within an effective mass approximation. The electron and hole bands touching at zero energy support chiral quasiparticles characterized by Berry’s phase Nπ for N-layers, generalizing the low-energy band structure of monolayer and bilayer graphene. We investigate the trigonal-warping deformation of the energy bands and show that the Lifshitz transition, in which the Fermi circle breaks up into separate parts at low energy, reflects Berry’s phase Nπ. It is particularly prominent in trilayers, N = 3, with the Fermi circle breaking into three parts at a relatively large energy that is related to next-nearestlayer coupling. For N = 3, we study the effects of electrostatic potentials which vary in the stacking direction, and find that a perpendicular electric field, as well as opening an energy gap, strongly enhances the trigonal-warping effect. In magnetic fields, the N = 3 Lifshitz transition is manifested as a coalescence of Landau levels into triply-degenerate levels.
AB - The electronic band structure of ABC-stacked multilayer graphene is studied within an effective mass approximation. The electron and hole bands touching at zero energy support chiral quasiparticles characterized by Berry’s phase Nπ for N-layers, generalizing the low-energy band structure of monolayer and bilayer graphene. We investigate the trigonal-warping deformation of the energy bands and show that the Lifshitz transition, in which the Fermi circle breaks up into separate parts at low energy, reflects Berry’s phase Nπ. It is particularly prominent in trilayers, N = 3, with the Fermi circle breaking into three parts at a relatively large energy that is related to next-nearestlayer coupling. For N = 3, we study the effects of electrostatic potentials which vary in the stacking direction, and find that a perpendicular electric field, as well as opening an energy gap, strongly enhances the trigonal-warping effect. In magnetic fields, the N = 3 Lifshitz transition is manifested as a coalescence of Landau levels into triply-degenerate levels.
KW - Berry phase
KW - effective mass
KW - energy gap
KW - Fermi level
KW - graphene
KW - Landau levels
KW - multilayers
UR - http://www.scopus.com/inward/record.url?scp=72849113995&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.80.165409
DO - 10.1103/PhysRevB.80.165409
M3 - Journal article
VL - 80
SP - 165409
JO - Physical review B
JF - Physical review B
SN - 1550-235X
IS - 16
ER -