1 research outputs found
Growth Instabilities as a Source of Surface Chemical Structuration in Functional Perovskite Thin Films
The spontaneous formation of double chemical
terminated surfaces of La0.7Sr0.3MnO3 due to deviations from
ideal epitaxial growth during its deposition on SrTiO3(001) is
presented. The development of surface regions with differentiated
topmost composition leads to outstanding surface
nanostructuration presenting notably distinct local properties,
particularly in terms of electric transport and local work
function. Correlation between combined atomic force
microscopy and X-ray photoelectron spectroscopy data allows
the chemical identification of the two terminations as
corresponding to La0.7Sr0.3O and MnO2. The most likely
atomistic process at the origin of the surface organization has
been interpreted by Monte Carlo simulations that reveal the
importance of stacking fault formation as growth proceeds. We present a physical understanding of the experimental results for
surfaces in which different electronic responses coexist. The conclusions of the present work can be extended to the growth of
other perovskite thin films, therefore broadening the field of functional materials nanostructuration.This work has been supported by the Spanish Government
under projects MAT2013-47869-C4 and MAT2015-71664-R.
The ICMAB members acknowledge the Spanish MINECO
through the project MAT2015-68994-REDC and the Severo
Ochoa Program (SEV-2015-0496), FEDER program and the
Generalitat de Catalunya through 2014 SGR 501. L.L.M. thanks
the Spanish MINECO for a FPI BES-2013-063424 fellowship.
J.J.M. thanks the Centro de Computacioń Cientıfí ca (CCC) of
the Universidad Autónoma de Madrid for computing time.Peer reviewe