Low-temperature magnetic properties of erbium doped bismuth nano-ferrites.

Nanocrystalline pure and erbium (Er³⁺)-substituted bismuth ferrite nanoparticles were synthesized by the citrate-gel auto-combustion method. Prepared powders were sintered at 500 °C for five hours in the air and characterized by XRD, TEM, and HR-TEM. X-ray diffraction (XRD) analysis showed the distorted rhombohedral structure of the ferrites. The surface morphology and particle size of the samples were observed by high-resolution transmission electron microscopy. The lattice parameter, crystalline size, X-ray density has been calculated from d-spacing. The perceived results can be explained depending on doping concentration. The temperature dependence of magnetic properties of Bi-Er nanoparticles was carried out by using a vibrating sample magnetometer (VSM). The magnetization as a function of applied field at ± 100 Oe was carried out at 3 and 300 K. Zero-field-cooled and (ZFC) and field-cooled (FC) magnetization measurements under an applied field of 100 Oe in the temperature range of 3-360 K. These measurements give the results of blocking temperature (T_b) at around 350 K. [ABSTRACT FROM AUTHOR]