AFM Observation of 90° Domains of BaTiO₃Butterfly Crystals

We used atomic force microscopy (AFM) to study the surface morphology of tetragonal barium titanate BaTiO 3 at room temperature. An undulation of the surface was observed around the boundary of 90° domains of the as-grown surface of the so-called butterfly crystals, which can be reasonably explained by the tetragonality of this crystal at room temperature.