Reversible manipulation of the magnetic state in SrRuO3 through electric-field controlled proton evolution

• Published in: Nature communications Vol. 11; no. 1; pp. 184 - 9
• Main Authors: Li, Zhuolu, Shen, Shengchun, Tian, Zijun, Hwangbo, Kyle, Wang, Meng, Wang, Yujia, Bartram, F. Michael, He, Liqun, Lyu, Yingjie, Dong, Yongqi, Wan, Gang, Li, Haobo, Lu, Nianpeng, Zang, Jiadong, Zhou, Hua, Arenholz, Elke, He, Qing, Yang, Luyi, Luo, Weidong, Yu, Pu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 10.01.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/119/2793; 639/766/119/995; 639/766/119/997; Carrier density; Concentration gradient; Electric fields; Electron states; Evolution; Ferromagnetism; Gating; Hall effect; Humanities and Social Sciences; Ionic liquids; Ions; MATERIALS SCIENCE; Materials substitution; multidisciplinary; Phase transitions; Protonation; Protons; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-13999-1

Ionic substitution forms an essential pathway to manipulate the structural phase, carrier density and crystalline symmetry of materials via ion-electron-lattice coupling, leading to a rich spectrum of electronic states in strongly correlated systems. Using the ferromagnetic metal SrRuO 3 as a model system, we demonstrate an efficient and reversible control of both structural and electronic phase transformations through the electric-field controlled proton evolution with ionic liquid gating. The insertion of protons results in a large structural expansion and increased carrier density, leading to an exotic ferromagnetic to paramagnetic phase transition. Importantly, we reveal a novel protonated compound of HSrRuO 3 with paramagnetic metallic as ground state. We observe a topological Hall effect at the boundary of the phase transition due to the proton concentration gradient across the film-depth. We envision that electric-field controlled protonation opens up a pathway to explore novel electronic states and material functionalities in protonated material systems. Ionic substitution is a useful way to manipulate structural, electronic, magnetic phase transitions in strongly correlated materials. Here, the authors report electric-field controlled protonation in SrRuO 3 , resulting in a large structural expansion and a ferromagnetic-to-paramagnetic phase transition.