Giant Induced Magnetization by Inverse Faraday Effect in α-W Thin Films

The inverse Faraday effect (IFE) is an optomagnetic phenomenon whose potential in controlling the magnetic properties in nanotechnology devices is quite appealing in the development of magnetic recording, quantum computation and spintronic technologies. In this work, we measure by time-resolved magneto-optic Kerr effect the ultra-fast optically induced magnetization by IFE on non-magnetic, sputtered grown α-W thin films, for photon energies between 1.2 – 1.7 eV. We observe an increase by an order of magnitude on the induced magnetization by IFE compared to other heavy metals with high spin-orbit coupling like Pt, Pd or β-W. This result represents an important stepping stone in the further development of magnetooptically controlled devices.