A new class of ferromagnetic semiconductors and quantum heterostructures

To integrate ferromagnetism and topological properties into mainstream semiconductors is highly challenging but potentially useful for new ultralow-power electronics and topological quantum computing. By doping Fe in narrow-gap III-V semiconductors such as InAs, GaSb and InSb using molecular beam epitaxy (MBE), we realized a new class of N-type and P-type ferromagnetic semiconductors (FMSs) with high Curie temperature (T
C
> 300 K) for the first time. Furthermore, heterostructures of these new Fe-doped FMSs exhibit various new phenomena such as giant proximity magnetoresistance and odd-parity magnetoresistance, all induced by a long-range magnetic proximity effect. These results suggest that the Fe-doped III-V FMSs are promising materials for high-performance spintronic devices.