Electronic properties of a biased graphene bilayer

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Eduardo V Castro (Author) Other; Novoselov, KS (Author) Other; Morozov, SV (Author) Other; Peres, NMR (Author) Other; Lopes dos Santos, JMBL (Author) FCUP; Johan Nilsson (Author) Other; Guinea, F (Author) Other; Geim, AK (Author) Other; Castro Neto, AH (Author) Other

Journal

Title: Journal of Physics Condensed Matter

Vol. 22

Final page: 175503

ISSN: 0953-8984

Publisher: Institute of Physics Publishing

Indexing

ISI Web of Knowledge - 153 Citations

Scopus - 193 Citations

Scientific classification

FOS: Natural sciences > Physical sciences

Other information

Authenticus ID: P-003-6SE

DOI: 10.1088/0953-8984/22/17/175503

Abstract (EN): We study, within the tight-binding approximation, the electronic properties of a graphene bilayer in the presence of an external electric field applied perpendicular to the system-a biased bilayer. The effect of the perpendicular electric field is included through a parallel plate capacitor model, with screening correction at the Hartree level. The full tight-binding description is compared with its four-band and two-band continuum approximations, and the four-band model is shown to always be a suitable approximation for the conditions realized in experiments. The model is applied to real biased bilayer devices, made out of either SiC or exfoliated graphene, and good agreement with experimental results is found, indicating that the model is capturing the key ingredients, and that a finite gap is effectively being controlled externally. Analysis of experimental results regarding the electrical noise and cyclotron resonance further suggests that the model can be seen as a good starting point for understanding the electronic properties of graphene bilayer. Also, we study the effect of electron-hole asymmetry terms, such as the second-nearest-neighbour hopping energies t' (in-plane) and gamma(4) (inter-layer), and the on-site energy Delta.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 14