Magnetic In(x)Ga(1 - x)N nanowires at room temperature using Cu dopant and annealing

Single-crystal, Cu-doped In(x)Ga(1 - x)N nanowires were grown on GaN/Al(2)O(3) substrates via a vapor-liquid-solid (VLS) mechanism using Ni/Au bi-catalysts. The typical diameter of the Cu:In(x)Ga(1 - x)N nanowires was 80 to 150 nm, with a typical length of hundreds of micrometers. The as-grown nanowires exhibited diamagnetism. After annealing, the nanowires exhibited ferromagnetism with saturation magnetic moments higher than 0.8 μ(B) (1 μ(B) × 10(-24) Am(2)) per Cu atom at room temperature by the measurements using a superconducting quantum interference device (SQUID) magnetometer. X-ray absorption and X-ray magnetic circular dichroism spectra at Cu L(2,3)-edges indicated that the doped Cu had a local magnetic moment and that its electronic configuration was mainly 3d(9). It possessed a small trivalent component, and thus, the n-type behavior of electrical property is measured at room temperature.