Ferromagnetic and Electrical Characteristics of in Situ Manganese-Doped GaN Nanowires

The ferromagnetic and electrical characteristics of in situ Mn-doped GaN nanowires fabricated in the absence of any catalyst are reported. The nanowires are of single-crystal hexagonal structure, containing Mn up to 2.5 atom %. Magnetism measurements indicate that the nanowires have room temperature ferromagnetism with Curie temperature above 350 K. Magnetic force microscopy verifies that the ferromagnetism of the individual nanowire is uniform along the nanowire. An electrical transport measurement reveals that the nanowire has a weak gating effect and is of the n-type.