Magnetic proximity effect between topological insulator (TI) and ferromagnetic insulator (FMI) is considered to have great potential in spintronics. However, a complete determination of interfacial magnetic structure has been highly challenging. We theoretically investigate the interlayer exchange coupling of two FMIs separated by a TI thin film, and show that the particular electronic states of the TI contributing to the proximity effect can be directly identified through the coupling behavior between two FMIs, together with a tunability of coupling constant. Such FMI/TI/FMI structure not only serves as a platform to clarify the magnetic structure of FMI/TI interface, but also provides insights into designing the magnetic storage devices with ultrafast response.
@article{arxiv.1407.6900,
title = {Magnetic Proximity Effect and Interlayer Exchange Coupling of Ferromagnetic/Topological Insulator/Ferromagnetic Trilayer},
author = {Mingda Li and Wenping Cui and Jin Yu and Zuyang Dai and Zhe Wang and Ferhat Katmis and Wanlin Guo and Jagadeesh Moodera},
journal= {arXiv preprint arXiv:1407.6900},
year = {2015}
}