Role of the Trigonal Warping on the Minimal Conductivity of Bilayer Graphene

作者：József Cserti, András Csordás, Gyula Dávid · 发表于：Physical Review Letters · 年份：2007 · DOI：10.1103/physrevlett.99.066802 · 被引用次数：134 · 研究领域：Graphene research and applications、Quantum and electron transport phenomena、Thermal properties of materials

Using a reformulated Kubo formula we calculate the zero-energy minimal conductivity of bilayer graphene taking into account the small but finite trigonal warping. We find that the conductivity is independent of the strength of the trigonal warping and it is 3 times as large as that without trigonal warping and 6 times larger than that in single layer graphene. Although the trigonal warping of the dispersion relation around the valleys in the Brillouin zone is effective only for low-energy excitations, our result shows that its role cannot be neglected in the zero-energy minimal conductivity.