Microwave Response of Gd-Doped YIG Based Y-Junction Stripline Circulator for Use at Very High Frequencies

摘要

This study aimed to evaluate the performance of microwave response of Gd-doped YIG. Gd-doped YIG consists of Yttrium Iron Garnet (YIG) magnetic ferrite with the existence of Gadolinium element into them. Lot of specimens were prepared through dry pressing technique and sintered into the high temperature tube furnace up to 1450°C. Sintering duration of 5 hours results the best magnetic properties. The existence of Gadolinium element tends to improve magnetic properties of magnetic ferrite Gd-doped YIG structure. Remacomp brand Magnet-Physik was used to determine the characteristics of soft magnetic materials in the measurement frequency range of 10 Hz to 70 kHz. Microwave response was measured using the Vector Network Analysis to provide insertion loss and isolation data. The obtained insertion loss of Gd_(0.75)Y_(2.25)Fe_5O_(12) is 0.4270 dB (at 3.7 GHz) and 0.2455 dB (at 4.2 GHz), while the isolation value is 11.3840 dB (at 3.7 GHz) and 17.8250 dB (at 4.2 GHz). The further experiment will be carried out to improve the microwave response and better magnetic properties of Gd-doped YIG structure.