Magnetic Phase Transitions in GdH0.15: Some Peculiarities in the Behavior of Magnetocaloric and Magnetostrictive Effects

Abstract

The magnetocaloric effect (MCE) and anomalies of magnetostriction behavior were studied at the order-order and order-disorder magnetic phase transitions in hydrided Gd single crystal grown by a modified Czochralski method. The composition GdH _0.15 was obtained using a Sievert-type apparatus. While parent Gd shows an isotropic MCE at the order-disorder phase transition, the effect is anisotropic in GdH _0.15 due to the appearance of local anisotropy. We investigate in detail the temperature variation of the longitudinal, transverse, volume, and anisotropic magnetostriction. Hydrogenation is found to influence both the magnitude and the sign of the magnetostriction constants $\lambda_{\rm ij}^{\alpha}$ .