Giant enhancement of spin pumping efficiency using Fe3Si ferromagnet

The generation, propagation, and control of spin current have attracted a great deal of attention because of the possibility of realizing dissipation-free information propagation. Although electrical generation of spin current originally made significant advances in spin-current devices, novel spin-current-generation approaches without the application of charge current, such as dynamical methods, have also been gaining importance. However, the low spin-current generation efficiency associated with dynamical methods has impeded further progress towards practical spin devices. Here we show that by introducing a single-crystalline ferromagnetic material, Fe3Si, pure spin currents can be generated about 20 times more efficiently when using a dynamical method. This achievement paves the way to the development of different spin-based devices.