Anomalously weak influence of source-drain voltage on inelastic scattering processes in quantum Hall systems

The inelastic scattering length Lᵢₙ of a two-dimensional electron gas in Al0.3Ga0.7As/GaAs heterostructure crystals at high magnetic fields is studied by analyzing the transition width between quantum Hall plateaus. The dependence of Lᵢₙ on the source-drain voltage VSD is found to be anomalously weak when compared to its dependence on the lattice temperature. The weak VSD dependence is attributed to the fact that in high magnetic fields the scattering-wave states of electrons incident on the conductor from the source contact is spatially separated from the states representing electrons incident on the conductor from the drain contact.