Researchers have discovered room temperature ferromagnetism in Co-doped anatase TiO₂ thin films. The study reports that Co-doped TiO₂ films with Co concentrations between 0 and 8% exhibit transparent ferromagnetism, with a magnetic moment of 0.32 Bohr magnetons per Co atom. The films are conductive and show a positive magnetoresistance of up to 60% at 2K. The ferromagnetism is attributed to the local spins of Co ions, and the material remains transparent in the visible and near-infrared regions, with a band gap of 400nm (3.1 eV). The Co-doped anatase films show ferromagnetic long-range order, with a Curie temperature estimated to be higher than 400K. The results suggest that the ferromagnetism arises from the combination of Co ions in the anatase structure, and the findings represent the first observation of magnetoresistance in anatase films. The study also highlights the potential of TiO₂ as a promising material for magneto-optical devices. The research was conducted using combinatorial screening and laser molecular beam epitaxy techniques, and the results are consistent with theoretical predictions. The study is significant as it opens up new possibilities for the development of spintronic devices and magneto-optical materials.Researchers have discovered room temperature ferromagnetism in Co-doped anatase TiO₂ thin films. The study reports that Co-doped TiO₂ films with Co concentrations between 0 and 8% exhibit transparent ferromagnetism, with a magnetic moment of 0.32 Bohr magnetons per Co atom. The films are conductive and show a positive magnetoresistance of up to 60% at 2K. The ferromagnetism is attributed to the local spins of Co ions, and the material remains transparent in the visible and near-infrared regions, with a band gap of 400nm (3.1 eV). The Co-doped anatase films show ferromagnetic long-range order, with a Curie temperature estimated to be higher than 400K. The results suggest that the ferromagnetism arises from the combination of Co ions in the anatase structure, and the findings represent the first observation of magnetoresistance in anatase films. The study also highlights the potential of TiO₂ as a promising material for magneto-optical devices. The research was conducted using combinatorial screening and laser molecular beam epitaxy techniques, and the results are consistent with theoretical predictions. The study is significant as it opens up new possibilities for the development of spintronic devices and magneto-optical materials.