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arXiv · 0809.1358

Critical thickness and orbital ordering in ultrathin La0.7Sr0.3MnO3 films

M. Huijben·L. W. Martin·Y. -H. Chu·M. B. Holcomb·P. Yu·G. Rijnders·D. H. A. Blank·R. Ramesh
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Abstract

Detailed analysis of transport, magnetism and x-ray absorption spectroscopy measurements on ultrathin La0.7Sr0.3MnO3 films with thicknesses from 3 to 70 unit cells resulted in the identification of a lower critical thickness for a non-metallic, non-ferromagnetic layer at the interface with the SrTiO3 (001) substrate of only 3 unit cells (~12 Angstrom). Furthermore, linear dichroism measurements demonstrate the presence of a preferred (x2-y2) in-plane orbital ordering for all layer thicknesses without any orbital reconstruction at the interface. A crucial requirement for the accurate study of these ultrathin films is a controlled growth process, offering the coexistence of layer-by-layer growth and bulk-like magnetic/transport properties.

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M. Huijben, L. W. Martin, Y. -H. Chu, M. B. Holcomb, P. Yu, G. Rijnders, D. H. A. Blank, R. Ramesh. 2008-09-08. Critical thickness and orbital ordering in ultrathin La0.7Sr0.3MnO3 films. https://doi.org/10.1103/physrevb.78.094413

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