Investigation of optimised YIG-Al substituted garnets in high-power below-resonance circulators

This paper presents some results of our investigation for finding an optimised garnet material suitable for ferrite devices operating at high power levels with the magnetic field polarities for below-resonance range. It is shown that by using an appropriate doping with rare-earth ions it is possible to achieve low-loss properties of a circulator both at low and at high power levels. The garnets were tested in waveguide and stripline circulators designed for L, S and C bands.