Direct Observation of Large Flexoelectric Bending at the Nanoscale in Lanthanide Scandates

Theoretical calculations and some experimental results have suggested that large bending of materials can take place at the nanoscale in response to an electric field, what is called the flexoelectric effect, but to date this has not been directly observed. We report here a direct observation of such large bending in three lanthanide scandates within a transmission electron microscope. The samples charge, and bend with a radius of curvature of the order of one micron. An extensive experimental characterization of the samples, both bulk and surface is described along with higher level density functional calculations.