Dresden 2017 – wissenschaftliches Programm
DF 18.3: Vortrag
Donnerstag, 23. März 2017, 15:30–15:45, WIL B321
Single domain multiferroic BiFeO3 films — •Chang-Yang Kuo1, Zhiwei Hu1, Jan-Chi Yang1, Tun-Wen Pi2, Stefano Agrestini1, Kai Chen3, Philippe Ohresser3, Arata Tanaka4, Liu Hao Tjeng1, and Ying-Hao Chu5 — 1MPI-CPfS, Dresden, Germany — 2NSRRC, Taiwan — 3Synchrotron SOLEIL, France — 4Hiroshima University, Japan — 5National Chiao Tung University, Taiwan
The strong coupling between antiferromagnetism and ferroelectricity at room temperature found in BiFeO3 generates high expectations for the design of technological devices. However, the multi-domain nature of the material tends to nullify the properties of interest and complicates the thorough understanding of the mechanisms involved. Here we report the realization of a BiFeO3 thin film which shows single domain behavior in both its magnetism and ferroelectricity: the entire film has its antiferromagnetic axis aligned along the crystallographic b-axis and its ferroelectric polarization along the c-axis. This allows us to reveal that the canted and net ferromagnetic moment due to the Dzyaloshinskii-Moriya interaction is parallel to the a-axis. Furthermore, by making a Co/BiFeO3 heterostructure, we successfully demonstrate that the ferromagnetic moment of the Co metal film couples directly to the canted ferromagnetic moment of BiFeO3. The realization of the single-domain multiferroic BiFeO3 films thus provides new insights into the fundamental interactions in this functional material and opens a promising path for the engineering of novel functional devices. C.Y. Kuo et al. Nature Communications, 7, 12712 (2016).