Low-temperature magnetic behavior of gadolinium ortho-ferrite and certain of its substitution compounds
Abstract
The rotational moments of gadolinium ortho-ferrite were measured in different crystallographic planes at 2.1°K. The rotation diagrams obtained indicate the presence of a magnetic ordering of the spins of the Gd3+ ions along the a axis of the crystal. A “flipping” of the Gd3+ antiferromagnetic sublattices was observed with the application of a magnetic field of ∼ 104 Oe along the a axis of the rhombic crystal. It is assumed that monoclinic distortions of the lattice occur during the ordering of the Gd3+ ions. The magnetization of GdFeO3, GdAl0.1Fe0.9O3 and GdGa0.1Fe0.9O3 were measured over the 4.2–80°K temperature range. It is shown that the spontaneous moment of the iron ions changes little with the partial substitution of Fe3+ ions by Ga3+ and Al3+ ions, while the effective field acting on the rare-earth ions, caused by the iron ions, increases. The possible cause of this phenomenon is discussed.