Elucidation of crystal and electronic structures within highly strained BiFeO3 by transmission electron microscopy and first-principles simulation

In-Tae Bae1, András Kovács2, Hong Jian Zhao3, Jorge Íñiguez3, Shintaro Yasui4,
Tomohiro Ichinose5 & Hiroshi Naganuma5,6


Abstract:

Crystal and electronic structures of ~380 nm BiFeO3 film grown on LaAlO3 substrate are
comprehensively studied using advanced transmission electron microscopy (TEM) technique combined with first-principles theory. Cross-sectional TEM images reveal the BiFeO3 film consists of two zones with different crystal structures. While zone II turns out to have rhombohedral BiFeO3, the crystal structure of zone I matches none of BiFeO3 phases reported experimentally or predicted theoretically.
Detailed electron diffraction analysis combined with first-principles calculation allows us to determine that zone I displays an orthorhombic-like monoclinic structure with space group of Cm (=8). The growth mechanism and electronic structure in zone I are further discussed in comparison with those of zone II.
This study is the first to provide an experimentally validated complete crystallographic detail of a highly strained BiFeO3 that includes the lattice parameter as well as the basis atom locations in the unit cell.

To download the article click on the link below:

http://scholar.google.com/scholar_url?url=https://www.nature.com/articles/srep46498.pdf%3Forigin%3Dppub&hl=fr&sa=X&scisig=AAGBfm33KlJLjQgayUFXMcCclfRkf4MFCA&nossl=1&oi=scholaralrt