▎ 摘　　要

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 pi e(2)/h 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. Copyright (C) EPLA, 2009