S. Methfessel, S. Middelhoek, et al.
Journal of Applied Physics
The systems EuSe - GdSe and EuS - GdS show a strong increase in the positive value of the paramagnetic Curie temperature (θ) as a function of the Gd3+ concentration. The pure europium chalcogenides in both systems have positive θ values. This paper discusses the effect of the increase of electron concentration on magnetic interactions in EuTe, which is antiferromagnetic in its pure state. We find that θ increases from -10°K for EuTe to a maximum of +28°K for Eu0.8Gd 0.2Te and then decreases monotonically with increasing Gd content to θ=-90°K for GdTe. The variation of θ is interpreted as a result of a Ruderman-Kittel-Yosida type interaction via the conduction electron donated by Gd3+. In contrast to the selenide and sulfide systems, no true ferromagnetic order occurs in EuTe-GdTe at 4.2°K for any composition. As an example, the magnetization of Eu0.8Gd0.2Te (θ=+28°K) saturates at 4.2°K for magnetic fields only above 45 000 Oe, which may be due to either spin canting or a more complex magnetic structure involving ferromagnetic clusters. © 1966 The American Institute of Physics.
S. Methfessel, S. Middelhoek, et al.
Journal of Applied Physics
J.R. Asik, R.J. Gambino, et al.
Journal of Applied Physics
R.J. Gambino, P. Fumagalll, et al.
IEEE Transactions on Magnetics
Y. Yeshurun, A.P. Malozemoff, et al.
Physical Review B