All-electric control of single atom spin states

In this talk I will review recent progress towards controlling the spins of individual atoms on a surface through local access with an STM probe tip. Magnetic d-metal atoms, separated from a metal substrate by a thin decoupling layer, are studied through inelastic electron tunneling spectroscopy (IETS): a tool by which transition energies of the spin state can be accurately followed. Combined with the possibility to rearrange the atoms at will so as to build multi-atom structures, this intriguing technique enables the investigation of magneto-crystalline anisotropy, spin coupling and the Kondo effect. By addressing atomic spins with a spin-filtered probe tip, controlled excitations or de-excitations can be made, effectively pumping the spin into a magnetization direction of choice. In a more recent experiment, spin pumping is performed in short pulses, opening up ways to control atomic spins in the time domain. I will discuss avenues to further develop this technique, potentially leading to the study of complex phases in extended magnetic lattices and coherent control of an atomic spin qubit.