Papers by Author: Yasuhiro Motoyoshi

Abstract: We performed first-principles calculations to examine the interaction among rare-earth (RE), alkaline-earth (AE) elements and oxygen vacancy (V_O) in BaTiO₃, in order to clarify the combined effects of V_O trapping by two different elements. It was found that there is a synergistic effect of V_O trapping by RE at Ba site and AE at Ti site, so that the co-doping is effective to improve insulating reliability of BaTiO₃. We also verified that the local atomic structures around dopants obtained by calculations well agree with that obtained experimentally by extended X-ray absorption fine structure (EXAFS) analyses. The present work is the first one to clarify the structural environment around dopants including V_O by both theoretical and experimental approaches.