Presentation Information
[1F10]Analysis of Fe electronic states in Bi0.8Ba0.2FeO2.9 and Bi0.8Ba0.2FeO2.8F0.2 thin films using X-ray spectroscopy
*Akiko Kamigaito1, Kei Shigematsu2, Masaki Kobayashi3, Hiroshi Kumigashira4, Kenta Amemiya5, Akira Chikamatsu1 (1. Department of Chemistry, Faculty of Science, Ochanomizu University, 2. Materials and Structures Laboratory, Institute of Integrated Research, Institute of Science Tokyo, 3. NTT Basic Research Laboratories, 4. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 5. Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization)
Multiferroic materials like BiFeO3 are promising for low-power magnetic devices, but its R3c structure causes complex switching. Ba and (Ba, F) co-doping aim to simplify this by forming a P4mm structure. While both Bi1-xBaxFeO3-x/2 and Bi1-xBaxFeO3-xFx (x = 0.2, 0.3) films showed magnetization at 300 K, only the F-doped films exhibited ferroelectricity. This study used RPES and XMCD to investigate Fe electronic states in Bi0.8Ba0.2FeO2.9 and Bi0.8Ba0.2FeO2.8F0.2. RPES revealed similar Fe 3d contributions in both, indicating no difference in magnetic sites. XMCD signals are detected at Fe L2,3-edges, showing both films are ferromagnetic. Peaks assigned to Fe3+ in octahedral (Oh) and tetrahedral (Td) sites suggest both contribute to magnetism. Thus, Ba and (Ba, F) co-doping yield similar magnetic behavior, while F suppresses leakage current, enabling coexistence of magnetism and ferroelectricity. The appealing point of this research is that the relationship between fluorine doping and the electronic state of iron, which was previously unknown, was clarified from the results of X-ray electron spectroscopy.