Low-energy band structure very sensitive to the interlayer distance in Bernal-stacked tetralayer graphene
Low-energy band structure very sensitive to the interlayer distance in Bernal-stacked tetralayer graphene
- 주제(키워드) A. Tetralayer graphene , B. Interlayer couplings , C. Metal-insulator transition , D. Quantum valley Hall effect
- 발행기관 한국물리학회
- 발행년도 2018
- 총서유형 Journal
- KCI ID ART002406757
- 본문언어 영어
초록/요약
We have investigated Bernal-stacked tetralayer graphene as a function of interlayer distance and perpendicular electric field by using density functional theory calculations. The low-energy band structure was found to be very sensitive to the interlayer distance, undergoing a metal-insulator transition. It can be attributed to the nearestlayer coupling that is more sensitive to the interlayer distance than are the next-nearest-layer couplings. Under a perpendicular electric field above a critical field, six electric-field-induced Dirac cones with mass gaps predicted in tight-binding models were confirmed, however, our density functional theory calculations demonstrate a phase transition to a quantum valley Hall insulator, contrasting to the tight-binding model prediction of an ordinary insulator.
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