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

The inelastic scattering length L-in of a two-dimensional electron gas in A l0.3Ga0.7As/GaAs heterostructure crystals at high magnetic fields is studie d by analyzing the transition width between quantum Hall plateaus. The depe ndence of L-in on the source-drain voltage V-SD is found to be anomalously weak when compared to its dependence on the lattice temperature. The weak V -SD dependence is attributed to the fact that in high magnetic fields the s cattering-wave states of electrons incident on the conductor from the sourc e contact is spatially separated from the states representing electrons inc ident on the conductor from the drain contact.