Title
Interface-induced multiferroism by design in complex oxide superlattices
Document Type
Article
Publication Date
6-27-2017
Abstract
Interfaces between materials present unique opportunities for the discovery of intriguing quantum phenomena. Here, we explore the possibility that, in the case of superlattices, if one of the layers is made ultrathin, unexpected properties can be induced between the two bracketing interfaces. We pursue this objective by combining advanced growth and characterization techniques with theoretical calculations. Using prototype LaSrMnO (LSMO)/BaTiO (BTO) superlattices, we observe a structural evolution in the LSMO layers as a function of thickness. Atomic-resolution EM and spectroscopy reveal an unusual polar structure phase in ultrathin LSMO at a critical thickness caused by interfacing with the adjacent BTO layers, which is confirmed by first principles calculations. Most important is the fact that this polar phase is accompanied by reemergent ferromagnetism, making this system a potential candidate for ultrathin ferroelectrics with ferromagnetic ordering. Monte Carlo simulations illustrate the important role of spin-lattice coupling in LSMO. These results open up a conceptually intriguing recipe for developing functional ultrathin materials via interface-induced spin-lattice coupling.
Publication Source (Journal or Book title)
Proceedings of the National Academy of Sciences of the United States of America
First Page
E5062
Last Page
E5069
Recommended Citation
Guo, H., Wang, Z., Dong, S., Ghosh, S., Saghayezhian, M., Chen, L., Weng, Y., Herklotz, A., Ward, T. Z., Jin, R., Pantelides, S. T., Zhu, Y., Zhang, J., & Plummer, E. W. (2017). Interface-induced multiferroism by design in complex oxide superlattices. Proceedings of the National Academy of Sciences of the United States of America, 114 (26), E5062-E5069. https://doi.org/10.1073/pnas.1706814114