Epitaxy and properties of InMnAsAlGaSb diluted magnetic III–V semiconductor heterostructures

InMnAsAlGaSb diluted magnetic semiconductor heterostructures have been grown by molecular-beam epitaxy on GaAs substrates. Three epitaxial procedures were employed for the growth of InMnAs, which resulted in three-dimensional or two-dimensional nucleation. Low-temperature magnetotransport measurements reveal that while some of the samples show well-aligned ferromagnetic ordering some others show ferromagnetic behavior with no magnetic anisotropy or, in the extreme case, superparamagnetic behavior. The transport properties were correlated to the growth modes.