On Magnetostriction of Gadolinium Iron Garnets

The temperature dependence of magnetostriction in the gadolinium ferrite having structure of a garnet has been measured within the temperature range from liquid nitrogen up to the Curie point. At temperatures above the compensation point of sublattices, θk, the magnetostriction isotherms are of the same kind as for ferromagnetics (λ∥ and λ⊥ have opposite signs and the λ vs H curves exhibit saturation). In cooling below, θk there is an effect of superposition of large volume magnetostriction of paraprocess on the “ordinary”magnetostriction, which results in the distortion of the magnetostriction isotherms (λ∥ and λ⊥ are of the same sign and without saturation). It is shown that the “ordinary” magnetostriction is caused by the interaction of >Fe3+ ions in sublattices a and d, while the volume magnetostriction of the paraprocess is caused by the interaction of Gd3+ and Fe3+ ions.