In the future, ultrahigh-speed spintronics will require ultrafast coherent magnetization reversal within a picosecond. While this may eventually be achieved via irradiation the small change of magnetization it generates has so far prevented any practical application of this technique. Now researchers report that they have explored ferromagnetic nanoparticles embedded within a semiconductor. Their theory was that the electric field of the terahertz pulse could be effectively applied to each nanoparticle.