Improving Microwave Response Performance through Involvement of Gadolinium Dopant into Yttrium Iron Garnet

In this study, the influence of gadolinium dopant composition on the microwave response performance of yttrium iron garnet was investigated. A hydraulic pressing was used to create the ferrite garnet sample. As the test material, pure oxide powder with an average grain size of 1 micron was employed. A pressure force of 700 MPa was used to compact the sample pellets. The sintering process was carried out in a high-temperature tube furnace at 1450 oC for five hours. This research shows that the calculated findings match the experimental data, demonstrating that the addition of gadolinium reduces the total magnetic moment and insertion loss of yttrium iron garnet. Adding 14 to 25% mol of gadolinium to one mol of iron oxide resulted in an insertion loss value near to zero, according to the calculations. To validate this calculation value, the microwave response of a sample of yttrium iron garnet with 15% mol of gadolinium doping was measured at frequency 4 GHz, yielding an insertion loss parameter value of 0.25 dB, which has a crucial function in lowering the insertion loss value of yttrium iron garnet.