ABSTRACT
Mn-doped GaAs nanowires were grown in the self-catalytic growth mode on the oxidized Si(100) surface by molecular beam epitaxy and characterized by scanning and transmission electron microscopy, Raman scattering, photoluminescence, cathodoluminescence, and electron transport measurements. The transmission electron microscopy studies evidenced the substantial accumulation of Mn inside the catalyzing Ga droplets on the top of the nanowires. Optical and transport measurements revealed that the limit of the Mn content for self-catalysed growth of GaAs nanowires corresponds to the doping level, i.e., it is much lower than the Mn/Ga flux ratio (about 3%) used during the MBE growth. The resistivity measurements of individual nanowires confirmed that they are conductive, in accordance with the photoluminescence measurements which showed the presence of Mn(2+) acceptors located at Ga sites of the GaAs host lattice of the nanowires. An anomalous temperature dependence of the photoluminescence related to excitons was demonstrated for Mn-doped GaAs nanowires.
ABSTRACT
It is shown that the growth of II-VI diluted magnetic semiconductor nanowires is possible by the catalytically enhanced molecular beam epitaxy (MBE). Zn(1-x)MnxTe NWs with manganese content up to x=0.60 were produced by this method. X-ray diffraction, Raman spectroscopy, and temperature dependent photoluminescence measurements confirm the incorporation of Mn(2+) ions in the cation substitutional sites of the ZnTe matrix of the NWs.