Effect of Gd < sup > 3+ < /sup > on dielectric and magnetic properties of Y < inf > 3 < /inf > Fe < inf > 5 < /inf > O < inf > 12 < /inf >

Abstract

The Gd3+ doped Y3-xGdxFe5O 12 (x=0.0, 0.05, 0.15, and 0.25) nanopowders were prepared using modified sol-gel route. The structural characterizations such as X-ray diffraction, transmission electron microscopy has been carried out. The nanopowders were sintered at 700 C/3 h. The lattice parameters and density of the samples were increased with an increase of Gd3+ concentration. The microstructure was analyzed using atomic force microscopy. The room temperature dielectric (ε′ and ε″) and magnetic (μ′ and μ″) properties were measured in the frequency range 5-50 GHz. with Gd3+ the dielectric properties were enhanced, but there is a decrease in the magnetic properties. The room temperature magnetization studies were carried out up to 1.5 T. the saturation and remnant magnetization were decreased with an increase of gadolinium concentration. These garnets have low permeability, low losses and a broad distribution of FMR line width which makes them a promising material for microwave devices can be used in the high frequency range i.e. up to 50 GHz. © 2013 Elsevier B.V.