Superconductivity<i>Versus</i>Ferromagnetism in Lanthanum-Gadolinium Alloys

Abstract

The differential paramagnetic susceptibility of samples of La--Gd alloys containing from 0.6 to 5.00% Gd was measured in the temperature range from 4.22 to 0.10 deg K. Matthias et al. have shown that the addition of small amounts of Gd to La produced solid solutions with unusual magnetic properties. Alloys containing up to O.90% Gd are superconductors with transition temperatures (T/sub e/) which decrease linearly with increasing Gd content. Alloys containing 3.0% or more Gd are ferronmagnetic with Curie temperatures which increase with increasing Gd content. The alloy containing 3.0% Gd becomes ferromagnetic at 1.3 deg K, the lowest temperature attained. Extrapolation of the data suggests that the T/sub c/ vs. % Gd curve and the Curie temperature vs. % Gd curve would intersect for an alloy of 1.25% at a temperature of 0.5 deg K. (A.C.)