The authors find that electric-field gating-controlled lithium intercalation can switch FeSe reversibly between a nonmagnetic superconducting state and a high-temperature superconducting ferromagnetic state. Further, scanning-SQUID magnetometry reveals that the ferromagnetic domains survive deep in the Meissner state and coexist spatially.
- Yi Hu
- Keyi Liang
- Ding Zhang