Interface-induced multiferroism by design in complex oxide superlattices

by H.W. Guo, Z. Wang, S. Dong, S. Ghosh, M. Saghayezhian, L. Chen, Y. Weng, A. Herklotz, T.Z. Ward, R. Jin, S.T. Pantelides, Y. Zhu, J. Zhang & E.W. Plummer Proceedings of the National Academy of Sciences 114, E5092 (2017).

Abstract: Developments in synthesis and characterization of artificially structured materials has greatly advanced the possibility to explore new states of matter in material science. Recent discoveries show that new quantum states can be achieved at hetero-interfaces with various electromagnetic and mechanical boundary conditions. It remains an open question on how to design ultrathin layers with properties inaccessible in bulk phases, which is amenable to technological applications. In this work, we grow heterostructures with extremely high quality interfaces, characterized by state-of-the-art atomically resolved electron microscopy and spectroscopy. This combination allows us to identify an interface-induced structure that stabilizes ferromagnetism. Coupled with theory, we provide conceptually useful recipe to design low-dimensional materials with novel functionalities, in line with the loop of “make, measure, model”.