An X-band tunable circulator based on Yttrium iron garnet thin film

The Yttrium iron garnet (YIG) is one kind of ferrite artificial materials that can facilitate miniaturization of devices. Tuning properties of the YIG microstrip circulator we designed and optimized were investigated under different external magnetization fields using a three dimensional finite-element method. By adjusting the DC magnetic field in the planar of the ferrite disc, the center frequency can be tuned from 8.93 to 12.04GHz and even dual-frequency bands were achieved, and the maximum isolation is −29dB. The ferrite circulator proposed here is feasible to realize the functions of routing, filtering and isolation through tuning magnetic field for applications.