Clusters and magnetism in epitaxial Co-doped TiO₂ anatase

The clusters and magnetism in epitaxial Co-doped TiO₂ anatase by oxygen plasma assisted molecular beam epitaxy were discussed. All incident Co segregated to the clusters yielding a nanoscale ferromagnetic phase that was not ferromagnetic in homogeneous films of the same Co concentration. The nucleation of the phase simultaneous with continuous epitaxial film growth was monitored to avoid drawing false conclusions about the films structure.