Spin reorientation in Tb1-xYxFe11Ti compounds

The Tb_1-xY_xFe₁₁Ti (x=0, 0.2, 0.4, 0.6 and 0.8) compounds have been studied in magnetization and AC-susceptibility measurements as a function of temperature. The results show that the Tb_1-xY_xFe₁₁Ti compounds with x=0, 0.2 and 0.4 undergo a spin reorientation of the axis-to-plane type (referred to decreasing temperature), while the samples with x=0.6 and 0.8 remain easy-axis compounds down to the lowest temperature measured (4.2 K). The spin-reorientation temperature, T_sr, is found to decrease with increasing Y content. The observed temperature dependence of the magnetic structure of this series of compounds has been analyzed on the basis of a crystal-field model with the following set of crystal-field parameters: B₂⁰=0.45 K, B₄⁰=-1.8×10^-4 K and B₆ ⁰=0 K