2008/07/09 by Numan Akdogan, Alexei Nefedov, Hartmut Zabel +8
Energy · Materials Science · Physics and Astronomy · #Chemical and Physical Properties of Materials #Cobalt #Ferromagnetism #Ion #Magnetic circular dichroism #Magnetic moment #Magnetization #Phase (matter) #Rutile #TiO2 Photocatalysis and Solar Cells #ZnO doping and properties #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1088/0022-3727/42/11/115005
published as J. Phys. D: Appl. Phys. 42, 115005 (2009) · 19 pages, 16 figures
arxiv created 2008/07/09 · openalex publication_date 2009/05/13 · arxiv updated 2010/04/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on structural, magnetic and electronic properties of Co-implanted TiO2 rutile single crystals for different implantation doses. Strong ferromagnetism at room temperature and above is observed in TiO2 rutile plates after cobalt ion implantation, with magnetic parameters depending on the cobalt implantation dose. While the structural data indicate the presence of metallic cobalt clusters, the multiplet structure of the Co L3 edge in the XAS spectra gives clear evidence for a substitutional Co 2+ state. The detailed analysis of the structural and magnetic properties indicates that there are two magnetic phases in Co-implanted TiO2 plates. One is a ferromagnetic phase due to the formation of long range ferromagnetic ordering between implanted magnetic cobalt ions in the rutile phase, and the second one is a superparamagnetic phase originates from the formation of metallic cobalt clusters in the implanted region. Using x-ray resonant magnetic scattering, the element specific magnetization of cobalt, oxygen and titanium in Co-implanted TiO2 single crystals are investigated. Magnetic dichroism was observed at the Co L edges as well as at the O K edge. The interaction mechanism, which leads to ferromagnetic ordering of substituted cobalt ions in the host matrix, is also discussed.