Strain-induced creation and switching of anion vacancy layers in perovskite oxynitrides

• Published in: Nature communications 2020-11, Vol.11 (1), p.5923-5923, Article 5923
• Main Authors: Yamamoto, Takafumi, Chikamatsu, Akira, Kitagawa, Shunsaku, Izumo, Nana, Yamashita, Shunsuke, Takatsu, Hiroshi, Ochi, Masayuki, Maruyama, Takahiro, Namba, Morito, Sun, Wenhao, Nakashima, Takahide, Takeiri, Fumitaka, Fujii, Kotaro, Yashima, Masatomo, Sugisawa, Yuki, Sano, Masahito, Hirose, Yasushi, Sekiba, Daiichiro, Brown, Craig M., Honda, Takashi, Ikeda, Kazutaka, Otomo, Toshiya, Kuroki, Kazuhiko, Ishida, Kenji, Mori, Takao, Kimoto, Koji, Hasegawa, Tetsuya, Kageyama, Hiroshi
• Format: Article
• Language: English
• Subjects: 140/131; 147/137; 639/638/263/915; 639/638/298/917; Ammonia; Anions; Chemical composition; Chemistry; Crystal structure; Design modifications; electronic materials; First principles; Heterostructures; Humanities and Social Sciences; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Lattice strain; Lattice vacancies; Materials science; multidisciplinary; Nitrogen; Oxides; Oxynitrides; Periodicity; Perovskites; Science; Science (multidisciplinary); solid-state chemistry; Substrates; Superlattices; Switching; Thin films
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-020-19217-7

Perovskite oxides can host various anion-vacancy orders, which greatly change their properties, but the order pattern is still difficult to manipulate. Separately, lattice strain between thin film oxides and a substrate induces improved functions and novel states of matter, while little attention has been paid to changes in chemical composition. Here we combine these two aspects to achieve strain-induced creation and switching of anion-vacancy patterns in perovskite films. Epitaxial SrVO 3 films are topochemically converted to anion-deficient oxynitrides by ammonia treatment, where the direction or periodicity of defect planes is altered depending on the substrate employed, unlike the known change in crystal orientation. First-principles calculations verified its biaxial strain effect. Like oxide heterostructures, the oxynitride has a superlattice of insulating and metallic blocks. Given the abundance of perovskite families, this study provides new opportunities to design superlattices by chemically modifying simple perovskite oxides with tunable anion-vacancy patterns through epitaxial lattice strain. Properties of perovskite oxides can be changed by manipulating anion-vacancy order patterns, but they are difficult to control. Here the authors show strain-induced creation and switching of anion vacancies in perovskite films in which the direction or periodicity of anion-vacancy planes is altered depending on the substrate employed.