▎ 摘　　要

We study the ballistic conductivity of graphene bilayer in the presence of next-nearest neighbor hoppings between the layers. An undoped and unbiased system was found in RUT G. and RYCERZ A., Phys. Rev. B, 89 (2014) 045421, to show a nonuniversal (length-dependent) conductivity sigma(L), approaching the value of sigma(star) = 3/pi similar or equal to 0.95 for large L. Here we demonstrate one-parameter scaling and determine the scaling function beta(sigma) = d ln sigma/d lnL. The scaling flow has an attractive fixed point (beta(sigma(star)) = 0, beta'(sigma(star)) < 0) reproducing the scenario predicted for random impurity scattering of Dirac fermions with Coulomb repulsion, albeit the system considered is perfectly ballistic and interactions are not taken into account. The role of electrostatic bias between the layers is also briefly discussed. Copyright (C) EPLA, 2014