Controlled doping of single crystalline diluted magnetic semiconductor Ga1−xMnxN nanowires

We report on the optical and magnetic properties of single crystalline dilute magnetic semiconductor Ga1−xMnxN nanowires. The nanowires were fabricated by chemical vapor transport process, and had diameters of <100 nm and length of several μm. Controlled doping of manganese in the range of x = 0.01-0.08 was successfully achieved by varying the processing conditions. X-ray diffraction and transmission electron microscopy observation showed that the nanowires are single crystalline without any secondary phases. Photoluminescence emissions of all the doped nanowires were red-shifted (2.8 eV) compare to pure gallium nitride nanowires (3.3 eV) at room temperature. Ferromagnetism up to room temperature was observed in GaN1−xMnxN nanowires with x > 0.04.