Article Sidebar

Submitted
Apr 25, 2017
Published
Jun 1, 2009
Download
PDF
Statistic
Read Counter : 390 Download : 724

Main Article Content

Abstract

The anisotropy of the Ho3+, Tb3+ and Tm3+ rare-earth ions in RFe2 compounds is investigated using the field dependence of the NMR spectra of 169Tm, 159Tb and 165Ho in polycrystalline TmFe2, TbFe2, HoFe2 and related pseudo-binary compounds. The very large hyperfine interaction in these ions dominates the NMR spectrum; the NMR frequencies in the 2 to 7 GHz range provide therefore a measure of the localized  moment and its orientation in the crystal field. We compare the NMR measurements to single ion computations that include magnetostriction.

 

KEYWORDS:  

Keywords

Cubic laves phases Rare-earth intermetallic Hyperfine splitting Magnetic anisotropy NMR.

Article Details

References

  1. AL ASSADI, K.F., MACKENZIE, I.S. and McCAUSLAND, M.A.H. 1984, Domain and domain-wall nuclear magnetic resonance of 265Ho in (Gd,Y)Fe2, J Phys F: Met. Phys 14, 525.
  2. BUNBURY, D.ST.P., CARBONI, C. and McCAUSLAND, M.A.H. 1989, Field dependence of the hyperfine splittings in holmium hydroxide J. Phys. Condens. Mat. 1, 1307.
  3. BUSHOW, K.H.J. 1977, Intermetallic compounds of Rare Earth and 3-d transition metals, Rep Prog Phys 40, 1179-1256.
  4. CARBONI, C., MACKENZIE, I.S. and McCAUSLAND, M.A.H. 1989, Nuclear Magnetic Resonance at microwave frequencies, Hyperfine Interactions 51, 1139.
  5. CARBONI, C., BUNBURY, D.ST.P. and McCAUSLAND, M.A.H. 2009, Crystal-field anisotropy of TmFe2, to be published.
  6. DE AZEVEDO, W.M., MACKENZIE, I.S. and BERTHIER, Y.J. 1985, NMR of 159TbFe2 and TbFe3, J Phys F. Met. Phys. 15, L243.
  7. DE AZEVEDO, W.M. 1986, The hyperfine interaction of terbium in magnetically ordered compounds, PhD thesis Manchester, UK.
  8. DUMESNIL, K., DUFOUR, C., MANGIN, PH. and ROGALEV., A. 2002, Magnetic springs in exchange coupled DyFe2-YFe2 superlattices: an element selective X-ray magnetic circular dichroism study, Phys. Rev. B, 65: 094401-094406.
  9. DE LA FUENTE., C., ARNAUDAS, J.I., CIRIA, M., DEL MORAL, A., DUFOUR, C., MOUGIN, A. and DUMESNIL, K. 2001, Magnetic and magnetoelestic behavior of epitaxial TbFe2-YFe2 bilayers, Phys. Rev. B 63: 054417-054427.
  10. FUJIWARA, A., ASAKURA, K., HARADA, I., OGASAWARA, H. and KOTANI, A. 2005, XMCD study on electronic and magnetic states of rare earth 5d electrons in Laves compounds RFe2, Phys. Scr. T115: 113-114.
  11. GERMANO, D.J. and BUTERA, R.A. 1981, Heat capacity of, and crystal-field effect in, the RFe2 intermetallic compounds, Phys. Rev. B, 24(7): 3912-3927
  12. GORDEEV, S.N., BEAUJOUR, J-M L., BOWDEN, G.J., RAINFORD, B.D., DE GROOT, P.A.J., WARD, R.C.C., WELLS, M.R. and JANSEN, A.G.M. 2001, Giant magnetoresistence by exchange springs in DyFe2-YFe2 superlattices, Phys. Rev. Lett. 87: 186808-186812.
  13. GRATZ, E., KOTTAR, A., LINDBAUM, A., MANTLER, M., LATROCHE, M., PAUL-BONCOUR, V., ACET, M., BARNER, C., HOLZAPFEL, W.B., PACHECO, V. and YVON, K. 1996, Temperature and pressure-induced structural transitions in rare-earth deficient RNi2 Laves phases, J. Phys.: Condens. Matter 8: 8351-8361.
  14. LEA, K.R., LEASK, J.M. and WOLF, W.P. 1962, The raising of angular momentum degeneracy of f-electron terms by cubic crystal field, Journal of the Physics and Chemistry of Solids, 23: 1381-1405.
  15. LEE, S.J., LANGE, R.J., CANFIELD, P.C., HARMON, B.N. and LYNCH, D.W. 2000, Optical and magneto-optical properties of RFe2 and RCo2, Phys. Rev. B, 61: 9669-9679.
  16. LI Y, CARBONI, C., ROSS, J.W., MCCAUSLAND, M.A.H. and BUNBURY, D.ST.P, 1996, Hyperfine fields at lanthanides nuclei in the intermetallic compounds RFe2, J Phys Condens. Matter 8, 865.
  17. MCMORROW, D.F., McCAUSLAND, M.A.H. and HAN, Z.P. 1989, Exchange and crystal field interaction of Ho3+ in GdAl2 : a single crystal NMR study, J Phys Condens. Matter 1: 10439-10458.
  18. McCAUSLAND, M.A.H. and MACKENZIE, I.S. 1979, Nuclear Magnetic resonance in Rare Earth metals, Adv. Phys. 28, 305.
  19. MOUGIN, A., DUFOUR, C., DUMESNIL, K. and MANGIN, P. 2000, Strain induced magnetic anisotropy in single crystal RFe2 (110) thin films, Phys. Rev. B, 62: 9517-9531.
  20. OSTER, J., WIEHL, L., ADRIAN, H. and HUTH, M. 2005, Magnetic and magnetoelastic properties of epitaxial (211)-oriented RFe2 thin films J. Mag. Mag. Mater., 292: 164-177.
  21. PARLEBAS, J.C., ASAKURA, K., FUJIWARA, A., HARAD, I. and KOTANI, A. 2006, X-ray magnetic circular dichroism at rare-earth L23 absorption edges in various compounds and alloys Physics Reports, 431-1, 1-38.
  22. PAUL-BONCOUR, V. 2004, Comparison of the influence of hydrogen on the magnetic properties of RMn2 and RFe2 Laves phase compounds, Journal of Alloys and Compounds, 367: 185-190.
  23. SAWICKKI, M., BOWDEN, G.J.,, DE GROOT, P.A.J., RAINFORD, B.D., BEAUJOUR, J-M L., WARD, R.C.C. and WELLS, M.R. 2000, Exchange springs in antiferromagnetically coupled DyFe3-YFe2 superlattices, Phys Rev B 62: 5817-5820.
  24. STEVENS, K.W.H. 1952, Matrix Elements and Operator Equivalents Connected with the Magnetic Properties of Rare-Earth Ions, Proc. Phys. Soc. A 65: 209-215.