Microstructural and Magnetic Properties of Holmium-substituted Yttrium Iron Garnets (Y3-xHoxFe5O12) Synthesized by Conventional Ceramic Method

Polycrystalline single-phase Holmium (Ho) substituted yttrium iron garnets (Y3-xHoxFe5O12), where (x = 0.1, 0.3, 0.6, 0.9, 1.5) were prepared by conventional ceramic technique. The crystalline structure and magnetic properties of the samples were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating samples magnetometer (VSM). XRD study showed well-defined peaks of Ho-YIG. X-ray diffraction data showed an increase of 66 nm to 113 nm in grain size with an increase in Ho composition from 0.1 to 1.5. The magnetic measurements showed that saturation magnetization (Ms) and retentivity increase with increasing Ho contents. There is a noticeable decrease in the coercivity with the increase of Ho composition. It is concluded that substitution of Ho makes the YIG better soft magnetic material which may be used in electronic devices for the microwave region as well as magnetic bubble domain type memories.