Transport properties of a quantum Hall ferromagnet in parabolic wells

We report on the observation of an anomalous resistance peak in a tilted magnetic field corresponding to the filling factors 2 and 4 in parabolic wells with different widths. This phenomenon is due to unpolarized ferromagnetic transitions in quantum Hall ferromagnets. We find that the effect is isotropic when an in-plane magnetic field is applied along and perpendicular to the current direction. Isotropic domain-wall transport is responsible for the magnetoresistance peak.