Crossover of the Hall-voltage distribution in AC quantum Hall effect

The distribution of the Hall voltage induced by low-frequency AC current is studied theoretically in the incoherent linear transport of quantum Hall systems. It is shown that the Hall-voltage distribution makes a crossover from the uniform distribution to a concentrated-near-edges distribution as the frequency is increased or the diagonal conductivity is decreased. This crossover is also reflected in the frequency dependence of AC magnetoresistance.