Abstract
The effect of annealing temperature on crystalline structure and magnetic behaviors are experimentally investigated for Co(Cr0.9Fe0.1)2O4 with cubic spinel structure (space group Fd3ˉm, No. 227). The average crystallite size shows an increase with the increased annealing temperature (700–1200 oC). Magnetic compensation effect and negative magnetization are observed in temperature dependent magnetization M(T) curves of samples S3-S6 with larger crystallite size, which are respectively characterized by M(T) = 0 and M(T) < 0 under a stable positive magnetic field of 100 Oe. However, the phenomena are absent in S1-S2 due to the reduction of spontaneous magnetization in samples with smaller crystallite size. Furthermore, magnetization reversal occurs to be almost the same as compensation temperature Tcomp characterized by an abrupt change in M(T) curves under a higher magnetic field. This work provides a route for the manipulation of magnetism or magnetization state by annealing the sample at different temperatures.
NSTL
Elsevier