Universal scaling for both isotropic and anisotropic irradiated superconductors

Current-voltage characteristics are investigated by transport measurements on heavy-ion irradiated Bi2Sr2CaCu2O8+δ (γ=380), Bi1.8Pb0.2Sr2CaCu2O8+δ (γ=60) and isotropic (K,Ba)BiO3 single crystals. In the range of magnetic fields from Bϕ/10 to Bϕ (where Bϕ is the matching field), the same scaling functions can be used to describe the transition in these systems. We obtain ν⊥=1.1±0.1, z=5.3±0.2 using α (≡ν∥/ν⊥)=2, in good agreement with numerical simulations for the case of strongly screened vortex line interactions. The most important finding is that the scaling laws of the I-V characteristics in these systems could be the same despite the difference in anisotropy.