Magnetocrystalline anisotropy of non-uniaxial R - T magnetic materials studied by the singular point detection technique: an application to compounds (R = Y or Gd and x = 0 or 1)

Abstract

The easy magnetization direction of lies within the basal plane over all magnetic ordering temperatures. A spinning-sample magnetic alignment technique was used to align the basal planes of fine single crystallites of (R = Y or Gd and x = 0 or 1) to be parallel to each other. The degree of magnetic alignment was checked by x-ray diffraction. The magnetocrystalline anisotropy field of has been determined by a singularity appearing in the curve of versus H measured on a magnetically aligned sample when an external field is applied perpendicular to aligned basal planes. The temperature dependence of the anisotropy fields was measured from 4.2 K up to the corresponding Curie temperatures. It was found that the Curie temperatures of compounds with R = Y or Gd were enhanced upon partial substitution of Fe by Ga. However, the magnetic anisotropy fields of Ga-containing compounds are smaller than those of the corresponding pure compounds at low temperatures.