Metal-insulator transitions between quantum Hall plateaus

Metal-insulator transitions between quantum Hall (QHE) plateaus due to inelastic scattering are discussed in a smooth random potential within the framework of semiclassical approximation. Inelastic scattering rates due to both electron-phonon and electron-electron interactions are calculated. The electron-phonon scattering rate is dramatically influenced by a strong magnetic field and is found to be linear in temperature for a wide range of temperatures, corresponding to an effective reduction of the Debye temperature. The electron-electron scattering rate is still proportional to the temperature squared. Applying these results to the temperature scaling exponent κ for the width of the transition region between QHE plateaus, we argue that is dictated by the inelastic scattering rate and the percolation length, instead of the localization length.