Magnetic properties as a function of temperature of La and Gd co-doped YIG nanoparticles

Abstract

This paper presents the behavior of saturation magnetization and other magnetic properties depending on the temperature variation from the nanoparticles of YIG doped and co-doped with Gd and La at different concentrations. The samples were prepared according to the sol–gel method, resulting in crystallite sizes ranging from 55 nm to 121.2 nm. X-ray diffraction measurements and microscopy show details of the structural characterization of the compounds. The magnetization values were measured as a function of the external magnetic field of up to 20 kOe at temperatures between 2K and 300K. The saturation magnetization varied between 25.23 emu/g and 29.10 emu/g, at 300K. At 2K, the variation occurs between 30.72 emu/g and 39.92 emu/g. The magnetic properties of compound, are high sensitivity to temperature variations and the results showed a weakened ferrimagnetic coupling with the dopant concentration. Also, changes in the cubic anisotropy constant with temperature were verified.

Keywords

• Bloch’s law
• Saturation magnetization
• YIG nanoparticles
• Cubic anisotropy
• Effective exchange