Ferromagnetism and Bound Magnetic Polaron Behavior in ${(\hbox {In}_{1-{\rm x}}\hbox {Co}_{\rm x})}_{2}\hbox {O}_{3}$

Bulk samples of (In_1-xCo_x)₂O₃ were prepared in single phase form for x=0.02 and 0.07 . The samples are found to be free from impurities such as Co₃O₄ and other cobalt oxides as per the detailed micro structural and Raman spectroscopic analysis. Temperature variation of magnetization upto 900 K for 0.3 T magnetic field and field variation of magnetization at different temperatures down to 20 K were measured. Both the samples are found to exhibit clear room temperature ferromagnetism. The increase in spontaneous magnetization, remanent magnetization and coercive field with decrease in temperature is explained in terms of magnetic anisotropy. The initial magnetization data could be fitted to the bound magnetic polaron model. A clear paramagnetic to ferromagnetic transition with T_C ≈ 718 K was observed. The Curie-Weiss law fit conform the ferromagnetic transition with effective magnetic moment value of 1.5 μ_B.