Influence of conduction via a channel of an impurity δ-layer on the magneto-quantum effects in AlGaAs/GaAs/AlGaAs heterostructures

摘要

The lateral magneto resistance of the multi-layer AlGaAs/GaAs/AlGaAs heterostructures with quantum wells and impurity δ-layers in the adjacent barriers has been studied at 4.2 K. It is shown that both the classical magnetoresistivity tensor components and the magneto-quantum effects in such structures considerably depend on the contribution to conduction from the channel with small mobility formed in the impurity δ-layer. The obtained results are analyzed within the frame of the model of electron transport via two parallel channels with different electron mobilities. Based on this model the electron concentration in both the structural and δ-layer quantum wells and the dependence of the components of the magnetoresistivity tensor, including the magneto-quantum effects, on magnetic field strength have been calculated for samples with different doping level and manifest a good agreement between experimental results and calculations.