The perfect atom sandwich requires an extra layer !

The perfect atom sandwich requires an extra layer ! - 19/08/2014

The recent years have seen the discovery of various exotic phenomena at complex oxide interfaces, which are expected to revolutionize various technological applications in electronics, spintronics and data-storage. Combined with their unique (multi-)functional properties, complex oxide heterostructures display some of the most chemically abrupt, atomically precise interfaces, which is advantageous when constructing new interface phases with emergent properties by juxtaposing incompatible ground states. One might assume that atomically precise interfaces result from stoichiometric growth. In a publication appearing in Nature Communications, we show that the most precise control is obtained utilizing deliberate and specific non-stoichiometric growth conditions. For the precise growth of Srn+1TinO3n+1 Ruddlesden-Popper (RP) phases, stoichiometric deposition leads to the loss of the first RP rock-salt double layer, but growing with a strontium-rich surface layer restores the bulk stoichiometry and ordering of the subsurface RP structure. These results dramatically expand the materials that can be prepared in epitaxial heterostructures with precise interface control – from just the n = 1 end members (perovskites) to the entire RP homologous series - enabling the exploration of novel quantum phenomena at a richer variety of oxide interfaces. (Figure : courtesy of Y. F. Nie)

Atomically precise interfaces from non-stoichiometric deposition, Y. F. Nie, Y. Zhu, C.-H. Lee, L. F. Kourkoutis, J. A. Mundy, J. Junquera, Ph. Ghosez, D. J. Baek, S. H. Sung, X. X. Xi, K. M. Shen, D. A. Muller, and D. G. Schlom, Nature Communications 5, 4530 (2014) [DOI: 10.1038/ncomms5530]

Highlighted in the News and Views “Oxide heterostructures: Atoms on the move” by Guus Rijnders

http://dx.doi.org/10.1038/ncomms5530