MAGNETOTRANSPORT STUDY IN SEMICONDUCTOR QUANTUM-WELL SYSTEMS

The electronic magnetotransport in semiconductor quantum wells is stud ied within the context of a many-body Green's function approach applic able in the presence of electric and magnetic fields. The regime studi ed ranges from 2-30 T and 0-15 kV cm(-1) for magnetic and electric fie lds respectively. The quantum wells specifically investigated are the AlxGa1-xAs/GaAs/AlxGa1-xAs and the GaAs/GayIn1-yAs/GaAs systems, for x = 0.27 and y = 0.87 Al and Ga concentrations, respectively, at low te mperature. The results obtained are compared with experimental data fo r both the longitudinal and transverse magnetoresistance when availabl e. The low magnetic held calculations include up to 60 Landau levels w hen the electron concentration is high. The quantum well potentials ar e modeled in a variational wavefunction scheme. The calculations inclu de electron scattering contributions due to impurities and phonons. (C ) 1998 Elsevier Science Ltd. All rights reserved.