Charge transfer is a common phenomenon at oxide interfaces. We use first-principles calculations to show that via heterostructuring of transition metal oxides, the electronegativity difference between two dissimilar transition metal ions can lead to high level of charge transfer and induce substantial redistribution of electrons and ions. Notable examples include i) designing a new Mott insulator via a charge-transfer-driven metal-insulator transition [1]; ii) tailoring magnetic structures and inducing interfacial ferromagnetism [2]; iii) engineering orbital splitting and inducing a non-cuprate single-orbital Fermi surface [3]. Utilizing charge transfer to induce emergent electronic/magnetic/orbital properties at oxide interfaces is a robust approach. Combining charge transfer with quantum confinement and epitaxial strain provides an appealing prospect of engineering electronic structure of artificial oxide heterostructures.
[1] H. Chen, A. J. Millis and C. A. Marianetti, PRL 111, 116403 (2013)
[2] H. Chen, H. Park, A. J. Millis and C. A. Marianetti, PRB 90, 245138 (2014)
[3] H. Chen, D. P. Kumah, A. S. Disa, F. J. Walker, C. H. Ahn, and S. Ismail-Beigi, PRL 110, 186402 (2013)
Hanghui Chen earned his B.S. in physics from Peking University and received his Ph.D in physics from Yale University in 2012. He is now a postdoctoral fellow in the Department of Physics at Columbia University, working with Professor Andrew Millis. In his thesis, Hanghui used ab initio calculations to study emergent properties at transition metal oxide interfaces. His current research interests are computational design of strongly correlated materials in bulk and nanostructured forms, aided with state-of-the-art first-principles methods and supercomputers.