Full Perpendicular Switching of Ferrimagnetic Order by Electric‐Field with Ultralow Assisting Magnetic Field

Abstract Electric‐field controlled reversible switching of perpendicular magnetization is highly appealing but extremely challenging for energy‐efficient spintronic devices. The recently reported multiferroic heterostructures composed of ferroelectrics and compensated ferrimagnets provide a promising route to achieve this long‐standing goal. However, a giant assisting magnetic field is demanded to ensure fully reversible switching of the perpendicular ferrimagnetic order by electric‐field, hindering further advances towards practical use. Here, it is shown that this challenge can be overcome by chemical doping of compensated ferrimagnets. Using binary GdFe alloys as the model system, it is shown that Mn dopants lead to an unprecedented decrease of magnetic coercive field near the compensation temperature. Consequently, an electric‐field‐controlled 180° reversal of perpendicular ferrimagnetic order is demonstrated with a high switching ratio (close to 100%) and good reversibility, under a record‐low assisting magnetic field of only 3 mT. This nonvolatile electric‐field control is achieved using volatile piezo‐strain, expanding the scope of strain‐mediated strategy. Moreover, a magnetic‐field‐free, electric‐field‐driven perpendicular magnetic switching is realized in the magnetic multilayers. These results open a new avenue towards achieving energy‐efficient spintronics controlled by pure electric‐field.