A short-period (BaTiO 3) 6/(SrTiO 3) 5 superlattice was characterized by x-ray diffraction and transmission electron microscopy. The superlattice is epitaxially oriented with the c axes of BaTiO 3 and SrTiO 3 normal to the (001) surface of the SrTiO 3 substrate. Despite the large in-plane lattice mismatch between BaTiO 3 and SrTiO 3 (∼2.2%), the superlattice interfaces were found to be nearly commensurate. The crystallographic c/a ratio of the superlattice was measured and the results agree quantitatively with first-principles calculations and phase-field modeling. The agreement supports the validity of the enhanced spontaneous polarization predicted for short-period BaTiO 3/SrTiO 3 superlattices.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)