Berlin 2012 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 22: Correlated Electrons: Low-dimensional Systems - Materials 1

TT 22.4: Vortrag

Mittwoch, 28. März 2012, 10:15–10:30, H 0104

Electrostatic doping of a Mott insulator in an oxide heterostructure: the case of LaVO₃/SrTiO₃ — •Andreas Müller¹, Hans Boschker², Florian Pfaff¹, Martin Kamp², Gertjan Koster², Guus Rijnders², Michael Sing¹, and Ralph Claessen¹ — ¹Physikalisches Insititut and Röntgen Research Center for Complex Material Systems, Universität Würzburg, D-97074 Würzburg, Germany — ²Faculty of Science and Technology and MESA⁺ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands

The discovery of a quasi-two-dimensional electron system at the interface between the two band insulators LaAlO₃ and SrTiO₃ has triggered intense investigations of oxide heterostructures with other material combinations. The hope is that by combining a polar overlayer with a non-polar substrate electronic reconstruction will lead to highly mobile interface charge carriers with special properties. The formation of a conducting interface layer in epitaxial LaVO₃/SrTiO₃, where LaVO₃ is a Mott insulator, is studied by transport measurements and hard x-ray photoelectron spectroscopy. We identify an insulator-to-metal transition above a critical LaVO₃ thickness with transport properties similar to those recently reported for LaAlO₃/SrTiO₃ interfaces. Interestingly, our photoemission measurements give evidence that electronic charge is transferred exclusively to the LaVO₃-side of the interface caused by an electronic reconstruction within the film itself. This opens the opportunity to study a band-filling controlled Mott transition induced by a purely electrostatic mechanism.