Field dependence of Young’s modulus in a gadolinium single crystal

The field dependence of Young’s modulus along the hexagonal c axis is measured in a gadolinium single crystal over a wide range of temperatures and magnitudes of the magnetic field aligned with the c axis. It is found that the isotherms of the field dependence of the ΔE effect in gadolinium are well approximated by a linear dependence on the square of the magnetization in both strong and weak strong magnetic fields, and also above and below the spin reorientation temperature. It is shown that the experimental trends obtained near the ferromagnetic transition can be interpreted within the approach based on the Landau theory of second-order phase transitions. The parameters of such an approach are determined for gadolinium on the basis of the experimental data. Zh. éksp. Teor. Fiz. 114, 2111–2121 (December 1998)