Electric-Field Control of the Orbital Occupancy and Magnetic Moment of a Transition-Metal Oxide.

By using soft-x-ray linear and magnetic dichroism on La_{0.825}Sr_{0.175}MnO_{3}/PbZr_{0.2}Ti_{0.8}O_{3} ferromagnetic-ferroelectric heterostructures we demonstrate a nonvolatile modulation of the Mn 3d orbital anisotropy and magnetic moment. X-ray absorption spectroscopy at the Mn L_{2,3} edges shows that the ferroelectric polarization direction modifies the carrier density, the spin moment, and the orbital splitting of t_{2g} and e_{g} Mn 3d states. These results are consistent with polar distortions of the oxygen octahedra surrounding the Mn ions induced by the switching of the ferroelectric polarization.