Complex oxides with tunable structures have many fascinating properties, including high-temperature superconductivity, colossal magnetoresistance, superior piezoelectric effect, and room-temperature magnetoelectric coupling. However, the high-quality complex oxide epitaxy with precisely controlled composition is still out of reach.  

High-quality single-crystalline epitaxial films are essential for exploring their fundamental sciences and technological applications. The composition of complex oxides, however, makes such epitaxial growth challenging via conventional physical vapor deposition. So there is a strong desire to develop alternative strategies enabling complex oxide epitaxy, especially via solution processing.

In this study, scientists try to demonstrate the potential of solution processing in large-scale complex oxide epitaxy and establish novel room-temperature magnetoelectric coupling in epitaxial BTFM–CTO film. They have successfully developed sol–gel-based complex oxide epitaxy for multiferroic BTFM–CTO solid solution in large area, enabling convenient compositional tuning in combination with strain engineering for magnetically switched polarization. The process is simple, fast, cost-effective, and can be easily scaled up for industrial applications, making it possible to explore a much wider space of composition, phase, and structure of complex oxides.

The full publication can be found here: https://academic.oup.com/nsr/article/7/1/84/5583233