Scaling of the quantum Hall plateau-plateau transition in graphene

We show that the width of the longitudinal magnetoconductivity peaks in graphene related to the $N=1$ Landau level displays a power-law type temperature dependence, $\ensuremath{\Delta}\ensuremath{\nu}\ensuremath{\propto}{T}^{\ensuremath{\kappa}}$, with $\ensuremath{\kappa}=0.37\ifmmode\pm\else\textpm\fi{}0.05$. Similarly, the derivative of the Hall conductivity at the plateau transition, $(d{\ensuremath{\sigma}}_{xy}/d\ensuremath{\nu})$, scales as ${T}^{\ensuremath{-}\ensuremath{\kappa}}$ with $\ensuremath{\kappa}=0.41\ifmmode\pm\else\textpm\fi{}0.04$ for both the first and second Landau levels of electrons and holes. These results confirm the universality of a critical quantum Hall scaling in the higher Landau levels of graphene. In the zeroth Landau level, however, $\ensuremath{\Delta}\ensuremath{\nu}$ and $d{\ensuremath{\sigma}}_{xy}/d\ensuremath{\nu}$ are essentially temperature independent, pointing toward a different type of scaling that is possibly governed by a temperature independent intrinsic length.