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arXiv · 0806.3619

X-ray study of structural domains in the near-surface region of SrTiO3-substrates with Y0.6Pr0.4Ba2Cu3O7$ / La2/3Ca1/3MnO3 superlattices grown on top

J. Hoppler·J. Stahn·H. Bouyanfif·V. K. Malik·B. D. Patterson·P. R. Willmott·G. Cristiani·H. -U. Habermeier·C. Bernhard
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Abstract

We investigated with synchrotron x-ray diffraction and reflectometry the formation of structural domains in the near-surface region of single crystalline SrTiO3 (001) substrates with Y0.6Pr0.4Ba2Cu3O7 / La2/3Ca1/3MnO3 superlattices grown on top. We find that the antiferrodistortive cubic-to-tetragonal transition, which occurs at T_STO = 104K in the bulk and at a considerably higher temperature of at least 120K in the surface region of SrTiO3, has only a weak influence on the domain formation. The strongest changes occur instead in the vicinitiy of the tetragonal-to-orthorhombic transition in SrTiO3 around 65K, where pronounced surface facets develop that reach deep (at least several micrometers) into the SrTiO3 substrate. These micrometer-sized facets are anisotropic and tilted with respect to one another by up to 0.5deg along the shorter direction. Finally, we find that a third structural transition below 30K gives rise to significant changes in the spread of the c-axis parameters. Overall, our data provide evidence for a strong mutual interaction between the stuctural properties of the SrTiO3 surface and the multilayer grown on top.

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J. Hoppler, J. Stahn, H. Bouyanfif, V. K. Malik, B. D. Patterson, P. R. Willmott, G. Cristiani, H. -U. Habermeier, C. Bernhard. 2008-08-28. X-ray study of structural domains in the near-surface region of SrTiO3-substrates with Y0.6Pr0.4Ba2Cu3O7$ / La2/3Ca1/3MnO3 superlattices grown on top. https://doi.org/10.1103/physrevb.78.134111

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