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Influence of manganese contamination on high-mobility GaAs/AlGaAs heterostructures

Klaus Wagenhuber·Hans-Peter Tranitz·Matthias Reinwald·Werner Wegscheider
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Abstract

Photoluminescence and magnetotransport measurements have been performed to assess the quality of modulation doped GaAs/AlGaAs heterostructures. The temporal evolution of the low-temperature electron mobility of samples prepared in a molecular beam epitaxy chamber containing manganese as a source material was studied. Mn contamination was identified to be responsible for the reduction of the electron mobility to 1 x 10^{6} cm^{2}/Vs and the appearance of a distinct photoluminescence band. In contrast, structures in which this signal is absent reach mobility values of 5.4 x 10^{6} cm^{2}/Vs. This directly proves that the epitaxy of high-mobility electron systems and structures containing GaMnAs layers, in principle, can be combined in one growth chamber.

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Klaus Wagenhuber, Hans-Peter Tranitz, Matthias Reinwald, Werner Wegscheider. 2004-04-06. Influence of manganese contamination on high-mobility GaAs/AlGaAs heterostructures. https://doi.org/10.1063/1.1782262

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