Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8149228 | Journal of Crystal Growth | 2016 | 20 Pages |
Abstract
Cu and Mn co-doped LiNbO3 films were deposited on Si (111) substrates by rf-magnetron sputtering. XRD shows a randomly oriented polycrystalline R3C structure of LiNbO3 was formed in the films annealed at 1000 °C for 1 h in air. XPS and XAFS determine that Mn2+ substitutes on the Li site with a Li vacancy and Cu2+ substitutes on the Nb site with an oxygen vacancy in the LiNbO3 lattice. SQUID measurements indicate that all the films exhibit room temperature ferromagnetism, attributed to a strong d-d electron interaction between Mn and Nb and the bound magnetic polarons resulting from the oxygen vacancies. The saturated magnetization increases but the atom magnetic moment decreases with increasing Cu content in the films. The drop of the atom magnetic moment may arise from the antiferromagnetic coupling among adjacent Cu ions and an antiparallel configuration between Cu2+ ions and their trapped electrons.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Dechong Bu, Yuting Fu, Ning Sun, Chunjing Li, Yanghua Li, Yukai An, Jiwen Liu,