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Atomic-Scale Measurement of Structure and Chemistry of a Single-Unit-Cell Layer of LaAlO3 Embedded in SrTiO3

Published online by Cambridge University Press:  04 March 2013

Chun-Lin Jia*
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany International Centre for Dielectric Research, Xi'an Jiaotong University, 710049 Xi'an, China
Juri Barthel
Affiliation:
Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Central Facility for Electron Microscopy (GFE), Aachen University (RWTH), 52074 Aachen, Germany
Felix Gunkel
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Regina Dittmann
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Susanne Hoffmann-Eifert
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Lothar Houben
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Markus Lentzen
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Andreas Thust
Affiliation:
Peter Grünberg Institute (PGI), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany Ernst Ruska-Centre (ER-C) for Microscopy and Spectroscopy with Electrons, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
*
*Corresponding author. E-mail: c.jia@fz-juelich.de, c.jia@mail.xjtu.edu.cn
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Abstract

A single layer of LaAlO3 with a nominal thickness of one unit cell, which is sandwiched between a SrTiO3 substrate and a SrTiO3 capping layer, is quantitatively investigated by high-resolution transmission electron microscopy. By the use of an aberration-corrected electron microscope and by employing sophisticated numerical image simulation procedures, significant progress is made in two aspects. First, the structural as well as the chemical features of the interface are determined simultaneously on an atomic scale from the same specimen area. Second, the evaluation of the structural and chemical data is carried out in a fully quantitative way on the basis of the absolute image contrast, which has not been achieved so far in materials science investigations using high-resolution electron microscopy. Considering the strong influence of even subtle structural details on the electronic properties of interfaces in oxide materials, a fully quantitative interface analysis, which makes positional data available with picometer precision together with the related chemical information, can contribute to a better understanding of the functionality of such interfaces.

Type
Materials Applications
Copyright
Copyright © Microscopy Society of America 2013

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