Abstract
Precision measurements of the effective mass in high-quality bilayer graphene using the temperature dependence of the Shubnikov–de Haas oscillations are reported. In the density range cm, both the hole mass and the electron mass increase with increasing density, demonstrating the hyperbolic nature of the bands. The hole mass is approximately 20–30% larger than the electron mass . Tight-binding calculations provide a good description of the electron-hole asymmetry and yield an accurate measure of the interlayer hopping parameter . Both and are suppressed compared with single-particle values, suggesting renormalization of the band structure of bilayer graphene induced by electron-electron interaction.
- Received 20 July 2011
DOI:https://doi.org/10.1103/PhysRevB.84.085408
©2011 American Physical Society