Magnetization and magnetic anisotropy of R2Fe14B measured on single crystals

Abstract

The temperature dependence of the saturation magnetization and the magnetocrystalline anisotropy field have been measured on single‐crystal samples of the R₂Fe₁₄B compounds for R=Y, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, and Tm from 4.2 K to the magnetic ordering temperatures. A spin reorientation transition of the Nd₂Fe₁₄B type has been found in Ho₂Fe₁₄B at 57.6 K in zero field. Another type of spin reorientation caused by anisotropy compensation between the Fe and the R sublattices exists in Er₂Fe₁₄B and Tm₂Fe₁₄B. The temperature dependence of the angle of the easy direction of magnetization from the c axis has been measured for R=Nd, Ho, Er, and Tm. The relation between the magnetocrystalline anisotropy and the sublattice magnetization is investigated by employing a simplified two‐sublattice molecular field model.