Magnetoionic Control of Spintronic Device using a Solid State Proton Pump

A spintronic device controls both the electrical charge and the spin of electrons to transmit, process, and store information. The control of electron spin provides additional degrees of freedom to modify the electric and magnetic properties of materials such as magnetic anisotropy. However, the development and integration of spintronic devices has been limited, in part, by the lack of a robust approach to electrically gate magnetism. Conventional approaches to gating magnetism either exhibit impractically small changes to the properties of a magnet or limited operating lifetime due to material degradation. Here, a magneto-ionic device operates using a hydrogen-gated magneto-ionic mechanism to overcome these shortcomings. A gate voltage applied to the magneto-ionic device causes protons to move towards a magnetic layer where the protons reduce to hydrogen. The presence of hydrogen and protons leads to large changes in the magnetic layer without degradation. This voltage-induced process is reversible.