Disorder induced reduction of the anomalous Hall voltage in proton and Ag²¹⁺- ion- irradiated Tl₂Ba₂CaCu₂O₈ epitaxial films

Abstract

The effects of structural disorder introduced by proton and heavy-ion irradiation on the mixed-state Hall resistivity (ρ_xy) of Tl₂Ba₂CaCu₂O₈ films are reported. The ρ_xy attains a peak negative value at a temperature T* where the vortex mobility is a rapidly varying function of temperature. At T* it also shows a universal inverse scaling with the normal-state resistivity of the material, which increases on irradiation. Our data suggest that a stronger downstream contribution to vortex velocity from the drift of the normal carriers in the core, dictates the sign of the Hall voltage as the overall carrier concentration in the materials is reduced by irradiation.