Influence of Ru on Magnetism of $R_{2}{\hbox {Fe}}_{17}$ ( $R={\hbox {Y}}$ , Lu, and Er)

The study of unusual influence of Ru substitution for Fe on magnetic properties of Lu₂Fe₁₇ is extended to a series of R₂Fe₁₇. The work is performed on single-crystalline samples of Lu₂Fe₁₆Ru, Y₂Fe_17-xRu_x(0 ≤ x ≤ 1) and Er₂Fe_17-xRu_x (x=0, 1) compounds. The collinear ferromagnetic ground state present in the R₂Fe₁₇ (Y and Lu) parent alloys is destroyed in R₂Fe_17-xRu_x, and antiferromagnetism is stabilized in the whole temperature range of magnetic order. The ordering temperatures of R₂Fe₁₆Ru (R=Y , Lu, Er) are 120 K, and no evidence of spontaneous magnetization is found in any of the alloys. The Fe sublattice in Er₂Fe₁₆Ru is most likely to be antiferromagnetic as well, however the type of magnetic order of the Er sublattice is not clear. All the compounds under study possess an easy-plane type of magnetic anisotropy and exhibit wide field-induced hysteretic transitions at low temperatures.