Antiferromagnetic order in (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5: High pressure study

E. A. Tereshina (1, 2) , A. V. Andreev (1) , J. Kamarád (1) , Olivier Isnard (3)

1 Institute of Physics [Prague]
2 UK - Univerzita Karlova [Praha, Česká republika] = Charles University [Prague, Czech Republic]
3 NEEL - MRS - Matériaux, Rayonnements, Structure

The antiferromagnetic state observed in Lu2Fe17 at elevated temperatures is stabilized down to the ground state in (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5. The Néel temperature TN decreases from 274 K in Lu2Fe17 to 247 and 208 K in (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5, respectively. Both compounds exhibit the easy-plane type of magnetic anisotropy and a metamagnetic transition at fields below 1 T. External pressure pushes the transition toward a higher field and reduces the magnetization as well as TN to 234 and 185 K for (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5, respectively, under pressure 0.8 GPa. The pressure and the substitution effects can be understood in terms of exchange interaction varying strongly with changes in the lattice parameter c for (Lu0.8Ce0.2)2Fe17, while for Lu2Fe16.5Ru0.5, the change in magnetic structure occurs due to the weakening of the positive exchange interaction as a result of the reduction in the Fe magnetic moments at 12 k sites.

Mots clés: Magnetic phase boundaries; Magnetic anisotropy; Exchange and superexchange interactions; Spin arrangements in magnetically ordered materials; Antiferromagnetics; High-pressure effects in solids and liquids; Inorganic compounds

Domaines: Science des matériaux [cond-mat.mtrl-sci]

E. A. Tereshina, A. V. Andreev, J. Kamarád, Olivier Isnard. Antiferromagnetic order in (Lu0.8Ce0.2)2Fe17 and Lu2Fe16.5Ru0.5: High pressure study. Journal of Applied Physics, 2009, 105, pp.07A747. ⟨10.1063/1.3075584⟩. ⟨hal-00984015⟩