We report the effects of C4C-irradiation on the superconducting properties of BaFe1:9Ni0:1As2 single crystal. The BaFe1:9Ni0:1As2 single crystal before and after C4C-irradiation was characterized by magnetic, magneto-transport and magneto-optical techniques over a wide range of magnetic fields (0–13 T) and temperatures (2–200 K). We demonstrate that the C4C-irradiation significantly enhances the in-field critical current density (by a factor of up to 1.5 at 5 K) and induces enhanced flux jumping at 2 K, with only a small degradation (by 0.5 K) of the critical temperature, Tc. The vortex phase diagram describing the evolution of the vortex-glass transition temperature with magnetic field and the upper critical field has been resolved for the C4C-irradiated sample. For temperatures below Tc, the resistivity curves and the pinning potential were found to show good scaling, using a modified model for vortex-liquid resistivity. The vortex state is three dimensional at temperatures lower than a characteristic temperature. Good agreement between the thermally activated flux flow model, which is usually employed to account for the resistivity in the vortex-liquid region, and the modified vortex-liquid model, has been observed.

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