Abstract
GaN whiskers with a high content of Mn doping have been synthesized via a simple evaporation process. The microstructures and magnetic properties of the as-synthesized Ga
1
−
x
Mn
x
N whiskers were studied by electron microscopy and superconducting quantum interference device (SQUID). The Ga
1
−
x
Mn
x
N whiskers were crystalline in the hexagonal structure and had the [2
1
0] direction as the preferential growth direction. The whiskers had diameters of ≈100
nm to several hundred nm and lengths up to tens of micrometers. Magnetic measurements showed that the as-synthesized Ga
1
−
x
Mn
x
N whiskers contained two ferromagnetic phases with the Curie temperatures at ≈57 and 325
K. Large coercivity of ≈5000
Oe for the samples was also observed at 5
K.