Two-carrier transport in epitaxially grown MnAs - art. no. 052408

Magnetotransport measurements of ferromagnetic MnAs epilayers grown by mole cular beam epitaxy reveal the presence of both positive and negative charge carriers. Electrical transport at high temperatures is dominated by holes and at low temperatures by electrons. We also observe distinct changes in t he magnetoresistance associated with the transition between the electron- a nd hole-dominated transport regimes. These results are of direct relevance to MnAs/semiconductor hybrid heterostructures and their exploitation in ele ctronic and optical spin injection experiments.