Equilibration length of edge states in a GaAs/InyGa1−yAs/AlxGa1−xAs quantum well

Abstract

We have investigated the nonequilibrium edge-state transport in a pseudomorphic GaAs/${\mathrm{In}}_{\mathrm{y}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{y}}$As/ ${\mathrm{Al}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As quantum well in the integer quantum-Hall regime. A large deviation of the quantized Hall resistance from the value expected for equilibrium transport is observed when the Landau level filling factor in the bulk region is 4. The dependences of the equilibration length on the number of occupied Landau levels and the variation of the magnetic field within a plateau region are found to be significantly large in comparison with those in GaAs/${\mathrm{Al}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As heterostructures.