Some features of Gd substituted garnet containing Co2+for latching phase shifter

One of the authors has demonstrated that the high-power capability of a latching phase shifter was remarkably enhanced by employing Co²⁺doped Gd YIG without any increase in the insertion loss. Investigations done so far on the insertion loss are not sufficient to describe this fact. A part of the results of the investigation concerning Co²⁺doped Gd YIG has been presented by Nicolas et al. The characteristics of the Co²⁺, doped Gd YIG have been studied in regard to a latching phase shifter by way of the precise measurement of the complex permeabilities. For the samples containing an appropriate amount of Co²⁺, the part of the insertion loss due to the anisotropy field has been proved to be eliminated, and the value of the spin-wave linewidth has suggested that high-power capability is enhanced. The coercive force indicates the minimum value at that content of Co²⁺, while the remanence ratio remains fairly constant. It is concluded that the materials containing an appropriate amount of Co²⁺are superior to those materials without Co²⁺in both the insertion loss and high-power capability.