Defect and interfacial structure of heteroepitaxial Fe3O4/BaTiO3 bilayers.
The defect and interfacial structure in a Fe3O4/BaTiO3 heteroepitaxial bilayer was investigated by scanning transmission electron microscopy. The results show that the Fe3O4 film grew epitaxially on BaTiO3. The orientation relationship between Fe3O4, BaTiO3 and MgO is [100]Fe3O4//[100]BaTi3O//[100]MgO and (010)Fe3O4//(010)BaTiO3//(010)MgO. An initial interfacial nucleation layer was formed that partially accommodated the lattice mismatch strain between BaTiO3 and MgO. This investigation indicates that the formation of this buffer layer provides a high-quality BaTiO3 surface for subsequent Fe3O4 growth, resulting in a semicoherent interface. The Fe3O4 surface is nearly atomically abrupt (roughness Rrms = 0.78 nm). The Fe3O4 film exhibits magnetic domains with a diameter in the range of 0.4-2 microm.
Xie
Sujing
S
Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, Illinois 60208-3108, USA. sujingxie@gmail.com
Sterbinsky
George E
GE
Wessels
Bruce W
BW
Dravid
Vinayak P
VP