Angle-dependent Hall effect and vortex dynamics in single-crystalline MgB₂ thin films

We have studied the angle-dependent Hall effect in single-crystalline MgB₂ thin films prior to and after Fe ion irradiation. The angle-dependent Hall scaling ρ _xy = Aρ ^β _xx shows a universal behavior, as scaling exponent β = 2 ± 0.2 holds even after various doses of irradiation. By applying the anisotropic mass scaling model, the magnetic field dependent resistivity curves measured under various angles were shown to potentially overlap on a main curve, except for the small angle region (called failed angles). Moreover, it was found that the failed angles decreased with increasing irradiation doses. This behavior could be well interpreted within the frame of theories on the Hall effect and vortex dynamics.