Ferromagnetism and bound magnetic polaron behavior in bulk Sn1−xCoxO2

Co doped bulk SnO2 based diluted magnetic semiconductors were prepared in single-phase form up to 10% of doping. The magnetic properties were studied from magnetization and electron spin resonance measurements. The magnetization of the 2% doped sample annealed under N2 gas atmosphere exhibited a saturation magnetization of 0.34μB/Co ion and it could be analysed based on the Brillouin function model by taking into account the ferromagnetic contribution. The magnetization versus field (MM–HH) curves for the other samples recorded at three different temperatures could be analyzed based on the bound magnetic polaron model. The variation of the spontaneous moment of the bound magnetic polaron with temperature and doping concentration is explained in detail.