MAGNETOSTRICTION IN SINGLE CRYSTAL TERBIUM

The temperature and magnetic field dependence of the magnetostriction of single crystal terbium metal was measured in the paramagnetic range from 230 to 370K in fields H up to 25 koe. The magnetostriction is found to vary as H squares over the temperature range within which the magnetic moment is linear with H. The magnetostriction is found to follow the temperature dependence as predicted by the one-ion theory of Callen and Callen. The strains were measured along particular crystallographic directions so as to permit an evaluation of the four l = 2 coefficients described by Callen and Callen. The magnitudes of the magnetostrictive strains are in order of magnitude and sign agreement with the atomic theory of Tsuya, Clark, and Bozorth. (Author) Master's thesis presented to the Maryland Univ., College Park. Prepared for presentation at Conference on Rare Earth Research, Ames, Iowa, Sep 65.