The study of novel physical properties appearing when two materials are interfaced has become one of the major fields of research in solid state physics over the last decade. For example, in the strive for novel non-silicon based electronics, the discovery of the formation of a conductive layer right at the interface region between 2 insulators (for example LaAlO3 and SrTiO3); a so-called two-dimensional electron gas (2DEG) or two dimensional electron liquid appears. Another important example of such emergent phenomena is the appearance of interface magnetism or superconductivity. As the materials involved in those new physical phenomena are often complex oxides, many factors such as strain, oxygen stoichiometry, cation intermixing, oxygen octahedral coupling.…[1,2] have to be considered when discussing their origin. The exact understanding of those phenomena is a key factor in order to turn these research ideas into working devices and in order to search for the most optimal materials.
In parallel, advances in electron microscopy instrumentation and techniques such as the introduction of aberration-correctors of the probe-forming lens have made it possible to achieve sub-angstrom spatial resolution allowing the study of materials on an atom column by atom column basis. High Angle Annular Dark Field (HAADF) combined with Annular Bright Field (ABF) imaging have made it possible to study and understand respectively the cationic and the oxygen sub-lattices in these materials.
As a first example, in the case of a (La,Sr)MnO3 (LSMO) film grown on a NdGaO3 (NGO) substrate, the magnetic easy axis of the LSMO film can be reversed by adding a SrTiO3 (STO) buffer layer between the substrate and the film. Using the statistical analysis of STEM ABF images, we could reveal that even one single STO layer is enough to remove the transferred octahedral tilt of NGO into the LSMO film reversing its magnetic easy axis from the a to the b axis(see ref 1 and figure 1).
In a second part, The appearance of superconductivity in a superlattice of (Sr,Ca)CuO2 (SCCO) and BaCuO2 (BCO) will be investigated. Comparing two different heterostructures where 8 layers of SCCO are sandwiched with STO (no superconductivity) and BCO (superconductivity) the effect of the structure of the different layers (orientation of the CuO2 in the form of planes or chains) on the appearance of superconductivity will be presented.
 Z. Liao, M. Huijben, Z. Zhong, N. Gauquelin, S. Macke, R. Green, S. van Aert, J. Verbeeck, G. Van Tendeloo, K. Held, G. A. Sawatzky, G. Koster & G. Rijnders, Nat. Mater. 15 (2016), p.425-431
 N. Gauquelin, E. Benckiser, M.K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H. –U. Habermeier, U. Kaiser, B. Keimer & G.A. Botton, Physical Review B 90 (2014), article 195140
J.V., G.V.T. and S.V.A. acknowledge funding from FWO projects G.0044.13N and G.0368.15N. N.G. and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. All authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2).
To cite this abstract:Nicolas Gauquelin, Sandra van Aert, Johann Verbeeck, Gustaff Van Tendeloo; Determining the structure/property relation at oxide interfaces by means of advanced TEM spectroscopy and imaging. The 16th European Microscopy Congress, Lyon, France. https://emc-proceedings.com/abstract/determining-the-structureproperty-relation-at-oxide-interfaces-by-means-of-advanced-tem-spectroscopy-and-imaging/. Accessed: December 14, 2019
EMC Abstracts - https://emc-proceedings.com/abstract/determining-the-structureproperty-relation-at-oxide-interfaces-by-means-of-advanced-tem-spectroscopy-and-imaging/