Localization Exponent for the Second Landau Level in the Quantum Hall Effect

At temperature above 1K, we measured the temperature dependence of the longitudinal and Hall resistivity ρ_xx,ρ_xy in the regime of the quantum Hall
plateau-to-plateau transitions. The localization exponent v is extracted with an approach based on the variable range hopping theory. We find the quantity v≈2.3 at the second Landau level, which is proven to be accurately universal.