Magnetism in n-type GaMnN grown by molecular beam epitaxy

We investigate the magnetic properties of a strongly n-type GaMnN alloy grown by molecular beam epitaxy. Transport, X-ray diffraction, and magnetic characterizations are presented. The carrier concentration and mobility obtained by Hall effect measurements are nearly constant with respect to temperature over the entire temperature range from 4 K to 300 K. Magnetometry data indicates a transition temperature at approximately 170 K with hysteresis measurements indicating magnetic behavior at least to 300 K. The role of alloy microstructure is investigated using X-ray diffraction and shows the possible presence of alternate phases giving rise to magnetization. In transport, we observe a linear Hall effect dependence on magnetic field strength.