Regensburg 2016 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DS: Fachverband Dünne Schichten
DS 35: Thin Film Characterisation: Structure Analysis and Composition II
DS 35.4: Talk
Wednesday, March 9, 2016, 15:45–16:00, H8
Depth-resolved image of the LaAlO3/SrTiO3 system from Resonant Soft X-ray Reflectivity — •Martin Zwiebler1, Fabio Miletto Granozio2, Emiliano Di Gennaro2, Jorge Enrique Hamann-Borrero1, Enrico Schierle3, Eugen Weschke3, Jochen Geck4, Marco Salluzzo5, and Umberto Scotti di Uccio5 — 1Leibniz Institute for Solid State and Materials Research, IFW-Dresden, Helmholtzstr. 20, 01069 Dresden, Germany — 2CNR-SPIN and Dipartimento di Fisica, Complesso universitario di Monte S.Angelo Via Cinti, 80126, Naples, Italy — 3Helmholtz-Zentrum Berlin für Materialien und Energie, Albert Einstein-Str. 15, 12489 Berlin, Germany — 4Universität Salzburg, Hellbrunner Str. 34, 5020 Salzburg, Austria — 52CNR-SPIN and Dipartimento di Fisica, Complesso universitario di Monte S.Angelo Via Cinti, 80126, Naples, Italy
When LaAlO3 is grown epitaxially on a 001 Ti-terminated SrTiO3 substrate, a conductive 2D electron system (2DES) emerges, even though both parent compounds are bulk insulators. The conductivity of the 2DES is (i) tunable using the field effect, (ii) very sensitive to photon irradiation and (iii) can even show superconductivity at low temperatures. The reasons for the emergence of the 2DES at the STO/LAO interface remain elusive. Popular and intensively discussed scenarios include the layer polarity change at the interface, chemical doping via oxygen vacancies, interdiffusion, and structural changes. Here we show depth-resolved spectroscopic information, obtained from Resonant Soft X-Ray Reflectivity at the Ti L2,3 edge. Our results provide new insights about chemical interdiffusion, charge accumulation and structural distortions in these systems, which clarify the emergence of the 2DES and its response to photon irradiation.