Magnetization and Electrical Resistivity of Gadolinium Single Crystals

Abstract

The magnetic moment of single-crystal Gd has been measured in fields from 0 to 18 kOe along the $〈0001〉$, $〈10\overline{1}0〉$, and $〈11\overline{2}0〉$ directions at temperatures from 1.4 to 900\ifmmode^\circ\else\textdegree\fi{}K. Small anisotropy was observed below the Curie temperature and the easy direction of magnetization was found to be a function of temperature. The absolute saturation magnetic moment was found to be 7.55 Bohr magnetons/atom. The saturation magnetization was observed to follow the ${T}^{\frac{3}{2}}$ law from 200 to 50\ifmmode^\circ\else\textdegree\fi{}K with a deviation from this law observed below 50\ifmmode^\circ\else\textdegree\fi{}K. A ferromagnetic Curie temperature of 293.2\ifmmode^\circ\else\textdegree\fi{}K is reported. The effective Bohr magneton number in the paramagnetic region is 7.98 and the paramagnetic Curie temperature is 317\ifmmode^\circ\else\textdegree\fi{}K. Electrical resistivity measurements were made from 4.2 to 380\ifmmode^\circ\else\textdegree\fi{}K on the $b$-axis and $c$-axis crystals. For the $b$ axis, the resistivity changes slope at 293.2\ifmmode^\circ\else\textdegree\fi{}K. The $c$ axis exhibits a small maximum at 292\ifmmode^\circ\else\textdegree\fi{}K and a shallow minimum at 340\ifmmode^\circ\else\textdegree\fi{}K.