The recent progress in spintronics opens up new directions for novel device concepts and fundamental understandings. This is possible because of magnetic insulators (MIs), which have paved the way toward pure spin current-based spintronics. MIs with perpendicular anisotropy expand the horizon further, enabling new functionalities such as low-power spin-orbit torque switching, high-speed domain-wall motion, high-frequency spin-orbit torque oscillation, etc. In this chapter, we review recent progress in spintronic experiments using barium hexagonal ferrite BaFe12O19—a magnetic insulator with perpendicular anisotropy. These results lay the foundation for using MIs with perpendicular anisotropy as a medium to develop new energy-efficient pure spin current-based electronics.
Part of the book: Magnetic Materials and Magnetic Levitation