@article{10902/34998,
year = {2009},
url = {https://hdl.handle.net/10902/34998},
abstract = {A new mechanism is proposed for the generation of self-assembled nanodots at the surface of a film based on spontaneous outcropping of the secondary phase of a nanocomposite epitaxial film. Epitaxial self-assembled Sr–La oxide insulating nanodots are formed through this mechanism at the surface of an epitaxial metallic ferromagnetic La₀.₇Sr₀.₃MnO₃ (LSMO) film grown on SrTiO₃ from chemical solutions. TEM analysis reveals that, underneath the La–Sr oxide (LSO) nanodots, the film switches from the compressive out-ofplane stress component to a tensile one. It is shown that the size and concentration of the nanodots can be tuned by means of growth kinetics and through modification of the La excess in the precursor chemical solution. The driving force for the nanodot formation can be attributed to a cooperative effect involving the minimization of the elastic strain energy and a thermodynamic instability of the LSMO phase against the formation of a Ruddelsden–Popper phase Sr₃Mn₄O₇ embedded in the film, and LSO surface nanodots. The mechanism can be described as a generalization of the classical Stranski–Krastanov growth mode involving phase separation. LSO islands induce an isotropic strain to the LSMO film underneath the island which decreases the magnetoelastic contribution to the magnetic anisotropy.},
organization = {We acknowledge the financial support from Spanish MEC (NANOARTIS, MAT2005-02047; NANOFUNCIONA, NAN2004-09133-CO3-01; NANO-SELECT, CSD2007-00041 FPU, AP2005-4669 FPU), Generalitat de Catalunya (Catalan Pla de Recerca SGR-0029 and CeRMAE), CSIC (PIFCANNAMUS) and EU (HIPERCHEM, NMP4-CT2005-516858). The Cs corrected F20-FEI electron microscope was used through the European project ESTEEM (contract no. 026019).},
publisher = {Wiley-VCH GmbH},
publisher = {Advanced Functional Materials, 2009, 19(13), 2139-2146},
title = {Spontaneous outcropping of self-assembled insulating nanodots in solution-derived metallic ferromagnetic La₀.₇.Sr₀.₃Mno₃ films},
author = {Moreno Sierra, César and Abellán, Patricia and Hassini, Awatef and Ruyter, Antoine and Pérez del Pino, Angel and Sandiumenge, Felip and Casanove, Marie-Jose and Santiso, José and Puig, Teresa and Obradors, Xavier},
}