Room-temperature ferromagnetism in transparent Mn-doped BaSnO3 epitaxial films

Room-temperature ferromagnetism was observed in transparent Mn-doped BaSnO3 (BSMO) films epitaxially grown on SrTiO3 substrates by pulsed laser deposition. X-ray photoelectron spectroscopy and X-ray absorption near-edge structure spectra analysis revealed that Mn2+ is the primary Mn ion in the BSMO films. The high saturated magnetization of BSMO films grown at a low oxygen pressure can be attributed to the effective exchange coupling interaction between oxygen vacancies and magnetic Mn ions. Further, the band gap energy of the BSMO films increases from 3.27 to 3.74 eV with decreasing growth oxygen pressure. The results demonstrate that Mn-doped BaSnO3 films may be useful in integrated magneto-optical device applications.