Direct observation of cationic ordering in double perovskite Sr₂FeReO₆ crystals.
Two kinds of Sr₂FeReO₆ (SFRO) samples, pristine SFRO and Re-excess SFRO, were prepared and we visualized the local atomic structure in terms of cationic ordering in the prepared SFRO samples via high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM). HAADF-STEM results demonstrated the high degree of cationic ordering maintains in both the pristine SFRO and Re-excess SFRO samples. On the other hand, defective structures such as antiphase boundary and Re-deficient phase were observed dominantly in the pristine SFRO, and thus the poor magnetic property in the pristine SFRO is attributed to those defective structures related with the frustrated Fe/Re ordering.
Advanced Characterization and Analysis Group, Korea Institute of Materials Science, Changwon 641-831, Republic of Korea. youngchoi@kims.re.kr
Si-Young
SY
Choi
Jong Bong
JB
Lim
Yuichi
Y
Ikuhara
Danilo
D
Suvorov
Jae-Ho
JH
Jeon