Researchers from MIT and the DoE Brookhaven National Laboratory designed a way to use hydrogen ions, drawn from airborne water molecules at room temperature, to electrically control magnetism in a thin magnetic film.

Water molecules - hydrogens ions, magnetic field switch image

The thin-film was made from cobalt, palladium and gadolinium oxide on a platinum base - and gold contacts. The hydrogen ions are used for reversible magneto-ionic switching in the thin film. This is the first time that scientists have demonstrated reversible “hydriding” of a heavy metal.