Time evolution of charge conductivity of graphene bilayersY.-X. Wang, L.-P. Shi and S.-J. Xiong
National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University Nanjing 210093, China
received 11 May 2009; accepted in final form 18 August 2009; published September 2009
published online 16 September 2009
We adopt the dynamical method developed to solve the charge transport properties in monolayer graphene system (LEWKOWICZ M. and ROSENSTEIN B., Phys. Rev. Lett., 102 (2009) 106802) to bilayer graphene. We calculate the energy and the current density evolving with time when an electron field is applied to the system at time t=0. The conductivity shows a rapid oscillation at the beginning (small t), but soon converges to a steady value which coincides with the optical conductivity study value. We suggest that the physical origin of the minimum conductivity can be rooted to the electron-hole pairs excited by the electron field and the coherent transport.
73.21.Ac - Multilayers.
73.23.Ad - Ballistic transport.
81.05.Uw - Carbon, diamond, graphite.
© EPLA 2009