A combined study has been made of the lattice location and hyperfine field of Yb implanted into Fe single crystals. The location has been determined by ion channeling and back-scattering, the hyperfine field by perturbed angular correlation (PAC) measurements on169Yb (decaying to excited states in169Tm). The channeling experiments indicate that initially about 60% of the Yb atoms occupy substitutional sites in the Fe lattice, while the remaining atoms are not in any specific crystallographic site. On annealing, Yb migrates from substitutional to non-substitutional sites. No Yb atoms remain substitutional after a 600°C anneal. By making PAC measurements at two temperatures for two γ-γ cascades in169Tm, it is found that the PAC pattern can be described using a combined static and time-dependent magnetic interaction. The PAC results show that the average hyperfine field and relaxation parameter decrease on annealing, and that the field disappears after a 600°C anneal. The correlation between the location and the hyperfine field is discussed. A comparison of the results with previous Mössbauer results for151Gd implanted in Fe, together with relaxation parameter measurements on a169Yb2O3 source, suggests that the non-substitutional Yb is internally oxidized in the Fe host.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics
- Condensed Matter Physics
- Physics and Astronomy(all)
- Electronic, Optical and Magnetic Materials