Exploiting interfacial and size effects to construct oxide superlattices with robust and tunable magnetoelectric properties at room temperature
Y. Yang, L. Bellaiche, and J. Íñiguez
Physical Review B, vol. 91, no. 7, p. 075423, 2015
We propose a strategy to create materials displaying robust and tunable magnetoelectric multiferroic properties at room temperature. The key idea is to construct heterostructures that combine two different constituents: (1) compound BiFeO3, which presents strong ferroelectric and antiferromagnetic orders well above room temperature, but displays a small magnetic moment, and (2) a ferromagnetic insulator (e.g., BiMnO3) that is only required to couple magnetically with BiFeO3. Our simulations show that it is possible to combine such materials to create superlattices that present (i) a room-temperature multiferroic state with relatively large magnetization (up to 0.3μB per transition metal atom, with the possibility to improve by finding a suitable replacement for BiMnO3), (ii) an amply customizable magnetic behavior, and (iii) a strong magnetoelectric coupling. Thus, the design strategy successfully addresses a great challenge in the area of magnetoelectric multiferroics, exploiting interfacial couplings and size (layer-thickness) effects to produce materials apt for applications.
doi:10.1103/PhysRevB.91.075423