A-site layer terminated perovskite substrate: NdGaO3

Abstract

A perovskite single-crystal substrate, NdGaO3 (001), was thermally annealed in air to give an atomically defined surface structure. From analysis with coaxial impact-collision ion scattering spectroscopy, the terminating atomic layer was identified to be NdO1+δ , i.e., the A-site oxide monolayer in perovskite ABO3. This result is contrary to the B-site oxide (BO2−δ) termination observed in other perovskite surfaces, such as wet etched SrTiO3 and LaAlO3 or annealed (LaAlO3)0.3–(Sr2AlTaO6)0.7 (LSAT).