Magnetotransport in a pseudomorphic GaAs/GaInAs/GaAlAs heterostructure with a Si delta-doping layer

M. van der Burgt; V. C. Karavolas; F. M. Peeters; J. Singleton; R. J. Nicholas; F. Herlach; J. J. Harris; M. Van Hove; G. Borghs

doi:10.1103/physrevb.52.12218

arXiv · cond-mat/9508147

Magnetotransport in a pseudomorphic GaAs/GaInAs/GaAlAs heterostructure with a Si delta-doping layer

M. van der Burgt·V. C. Karavolas·F. M. Peeters·J. Singleton·R. J. Nicholas·F. Herlach·J. J. Harris·M. Van Hove·G. Borghs

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Abstract

Magnetotransport properties of a pseudomorphic GaAs/Ga0.8In0.2As/Ga0.75Al0.25As heterostructure are investigated in pulsed magnetic fields up to 50 T and at temperatures of T=1.4 K and 4.2 K. The structure studied consists of a Si delta-layer parallel to a Ga0.8In0.2As quantum well (QW). The dark electron density of the structure is n_e=1.67x 10^16 m^-2. By illumination the density can be increased up to a factor of 4; this way the second subband in the Ga0.8In0.2As QW can become populated as well as the Si delta-layer. The presence of electrons in the delta-layer results in drastic changes in the transport data, especially at magnetic fields beyond 30 T. The phenomena observed are interpreted as: 1) magnetic freeze-out of carriers in the delta-layer when a low density of electrons is present in the delta-layer, and 2) quantization of the electron motion in the two dimensional electron gases in both the Ga0.8In0.2As QW and the Si delta-layer in the case of high densities. These conclusions are corroborated by the numerical results of our theoretical model. We obtain a satisfactory agreement between model and experiment.

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M. van der Burgt, V. C. Karavolas, F. M. Peeters, J. Singleton, R. J. Nicholas, F. Herlach, J. J. Harris, M. Van Hove, G. Borghs. 1995-09-03. Magnetotransport in a pseudomorphic GaAs/GaInAs/GaAlAs heterostructure with a Si delta-doping layer. https://doi.org/10.1103/physrevb.52.12218

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