Cyclotron resonance in InGaAs/AlAs superlattices underpulsed high magnetic fields

摘要

We have carried out cyclotron resonance (CR) measurement in InGaAs/AlAsrnsuperlattices (SLs) under pulsed high magnetic fields to evaluate the effective mass ofrnelectrons. Clear CR signals were observed in the transmission from a far-infrared laser atrnroom temperature. We obtained that the cyclotron mass of (InGaAs)n/(AlAs)n SLs withrnn=6～12 monolayer in the parallel direction to the SL heterointerface are 0.073～0.080m0.rnBy comparing with result of GaAs/AlAs SLs, the observed signals suggest that Γ-X crossoverrnin the (InGaAs)n/(AlAs)n SLs occurs at around n=6 monolayer. We have also performed CRrnmeasurement to tilt the samples for different angle μ between the magnetic field and the normalrnto the SL heterointerface. A deviation of the CR peak position from a simple cos θ-dependencernwere observed, which suggested the Landau-level-miniband mixing in the SL under magneticrnfield.