  Controlling magnetism by electric fields offers a highly attractive
perspective for designing future generations of energy-efficient information
technologies. Here, we demonstrate that the magnitude of current-induced
spin-orbit torques in thin perpendicularly magnetized CoFeB films can be tuned
and even increased by electric field generated piezoelectric strain. Using
theoretical calculations, we uncover that the subtle interplay of spin-orbit
coupling, crystal symmetry, and orbital polarization is at the core of the
observed strain dependence of spin-orbit torques. Our results open a path to
integrating two energy efficient spin manipulation approaches, the electric
field-induced strain and the current-induced magnetization switching, thereby
enabling novel device concepts.
