Synchrotron X-ray diffraction study of SrRuO<Subscript>3</Subscript>/SrTiO<Subscript>3</Subscript>/SrRuO<Subscript>3</Subscript> nano-sized heterostructures grown by laser MBE

Structural investigation using X-ray synchrotron radiation has been performed on SrRuO<Subscript>3</Subscript>/SrTiO<Subscript>3</Subscript>/SrRuO<Subscrip t>3</Subscript> epitaxial heterostructures, with each constituent layer a few unit cell thick grown on (001) SrTiO<Subscript>3</Subscript> substrate. Detailed information on the evolution of the in-plane lattice structure has been obtained, in these heterostructures, by grazing incidence diffraction measurements. The samples have been grown by low-pressure pulsed laser deposition. Under our deposition conditions, SrRuO<Subscript>3</Subscript> layers grow with an elongated cell perpendicular to the substrate surface. The in-plane pseudocubic lattice parameters do not match the in-plane square SrTiO<Subscript>3</Subscript> structure even in the case of very thin SrRuO<Subscript>3</Subscript> layers. Such a distortion was found to decrease with increasing the thickness of the SrTiO<Subscript>3</Subscript> barrier layer. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005