ИСТИНА

The magnetism of diluted magnetic semiconductor (Ga,Cr)N is studied. The ion implantation was used to produce the chromium-doped GaN samples, the investigation of magnetic and magnetooptical properties was performed at the temperature 50-400 K. We observed the ferromagnetic behavior at the whole studied temperature range with high room-temperature magnetization of 25 G. Spectra of the magnetooptical transversal Kerr effect have revealed a strong magnetic response in the energy range less than 3.0 eV due the appearance of new spin-polarized states in the band gap of GaN upon Cr doping. The coercivity and saturation field have been reduced slightly after the vacuum annealing at the temperature 850 °C which is the consequence of a decrease of radiation defects in the material. The origin of magnetism is discussed.