Last months edition of Nature Nanotechnology sees the latest advancement in the use of femtosecond lasers to drive spin currents. Kampfrath et al. demonstrate both numerically and experimentally that it is possible to drive spins from a ferromagnetic iron thin film into a non-magnetic cap layer that has either low (ruthenium) or high (gold) electron mobility. The resulting transient spin current is detected by means of an ultrafast, contact-less amperemeter based on the inverse spin Hall effect, which converts the spin flow into a terahertz electromagnetic pulse.
The full details can be found at the Nature Nanotechnology website via the link here.