High-Field Magnetization Study of $$R_{2}\hbox {Fe}_{17}\hbox {N}_{2}$$ R 2 Fe 17 N 2 ( $$R = \hbox {Ho}$$ R = Ho and Er) Nitrides

Autor: I. A. Pelevin, A. A. Salamova, I. S. Tereshina, Mathias Doerr, J. M. Law, E.A. Tereshina-Chitrova, V. N. Verbetski
Rok vydání: 2017
Předmět:
Zdroj: Journal of Low Temperature Physics. 190:236-243
ISSN: 1573-7357
0022-2291
DOI: 10.1007/s10909-017-1838-3
Popis: The structure and magnetic properties of the nitrided compounds $$R_{2}\hbox {Fe}_{17}\hbox {N}_{2}$$ ( $$R = \hbox {Ho}$$ and Er) are studied. The type of crystal structure $$\hbox {Th}_{2}\hbox {Ni}_{17}$$ is preserved upon nitrogenation, and the relative unit cell volume $$\Delta V{/}V$$ increase exceeds 6%. Magnetic studies are performed in fields up to 60 T at 4.2 K on aligned powder samples. Field-induced spin-reorientation (SR) transitions are observed in the M(H) curves of $$R_{2}\hbox {Fe}_{17}\hbox {N}_{2}$$ . Unlike the parent $$R_{2}\hbox {Fe}_{17}$$ compounds, where the magnetization increases in steps as the field grows stronger, $$R_{2}\hbox {Fe}_{17}\hbox {N}_{2}$$ demonstrate a gradual increase in magnetization. It is indicative of the change of the SR transition from first to the second type. Extrapolation of magnetization curves to the theoretical value of magnetization in the forced ferromagnetic state yields the coefficient of the inter-sublattice R–Fe exchange interaction. The inter-sublattice exchange is found to decrease upon nitrogenation.
Databáze: OpenAIRE