Room temperature magnetization measurements of some substituted rare earth iron garnets

The saturation magnetization (M-s) and the initial magnetic susceptibility (chi (in)) of substituted yttrium iron garnet (YIG) Ho3-x Y-x Fe5O12 where (x=0,0.3,1.5), pure terbium iron garnet Tb3Fe5O12, and substituted aluminum iron garnet (AlIG) Ho3Fe5-x Al (x) O-12 where (x=0.05,0.7) at room temperature are reported. It has been observed that M (s) and chi (in) decrease in a linear manner as Ho3+ stop replaces Y3+ in yttrium iron garnet. For substituted (AlIG), a drastic decrease in both M (s) and chi (in) as Al3+ ions replace Fe3+ ions. The rate of decrease of M (s) and chi (in) with the increase of Al3+ for substituted (AlIG) is greater than that for substituted (YIG). That is attributed to the decrease in the superexchange interaction (self and mutual iron interactions) with Al substitution.