Nanoscale self-templating for oxide epitaxy with large symmetry mismatch
  Direct observations using scanning transmission electron microscopy unveil an intriguing interfacial bi-layer that enables epitaxial growth of a strain-free, monoclinic, bronze-phase VO2(B) thin film on a perovskite SrTiO3 (STO) substrate. We observe an ultrathin (2-3 unit cells) interlayer best described as highly strained VO2(B) nanodomains combined with an extra (Ti,V)O2 layer on the TiO2 terminated STO (001) surface. By forming a fully coherent interface with the STO substrate and a semi-coherent interface with the strain-free epitaxial VO2(B) film above, the interfacial bi-layer enables the epitaxial connection of the two materials despite their large symmetry and lattice mismatch. 
Xiang Gao, Shinbuhm Lee, John Nichols, Tricia L. Meyer, Thomas Z.   Ward, Matthew F. Chisholm, and Ho Nyung Lee
cond-mat.mtrl-sci