Morphology and magnetic properties of InMnAs nanodots and nanowires with ultrahigh Mn concentrations

Abstract

In1-xMnxAs (0.22≤x≤0.55) nanostructures with ultrahigh Mn concentration were grown on GaAs(001) substrates by molecular beam epitaxy. When the growth is performed at 380 C, nanodots are obtained. The M(T) relation of InMnAs nanodots is highly dependent on the morphology which is affected by Mn concentration. When the growth temperature is higher up to 550°C, the shape transition from nanodots to nanowires takes place and well-shaped nanowires are obtained at high Mn concentrations. The formation of InMnAs nanowires brings about the in-plane uniaxial magnetic anisotropy, with the easy axis along the self-alignment orientation, namely, 1 - 10 GaAs. © 2011 American Institute of Physics.