Dresden 2026 – wissenschaftliches Programm

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

HL: Fachverband Halbleiterphysik

HL 40: Oxide Semiconductors: Transport and Spectroscopy

HL 40.1: Vortrag

Donnerstag, 12. März 2026, 09:30–09:45, POT/0251

Unraveling metal-induced redox mechanisms on SrTiO3 via combined in-situ laser reflectometry and x-ray photoelectron spectroscopy — •Georg Hoffmann, Shi-Hui Liu, Serkan Sirt, Oliver Bierwagen, and Roman Engel-Herbert — Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e.V., Hausvogteiplatz 5-7, 10117 Berlin, Germany

SrTiO3 has long served as a key platform for emergent phenomena in perovskite oxides such as polar discontinuity driven two-dimensional electron gases (2DEGs) when interfaced with LaAlO3 [1]. Recently, increasing attention has been brought to 2-DEGs that emerge at SrTiO3 surfaces from redox-reactions induced by amorphous metal deposition on top [2]. Studying these processes, however, requires complex in-situ techniques like photoelectron spectroscopy (XPS) with long measurement cycles. Here, we introduce laser reflectometry (LR) as a complementary technique that enables monitoring of redox-reactions at oxide/metal interfaces. We show that LR in an oxide molecular beam epitaxy setup can distinguish between Al deposition on non-reactive substrates and Al oxidation, e.g. through oxygen scavenging from SrTiO3. Atomic force microscopy, Capacitance-Voltage profiling, and XPS measurements corroborate our findings. Our results demonstrate how LR can guide future investigations of redox-reactions at oxide/metal interfaces. [1] A. Ohtomo, and H. Y. Hwang., Nature 427, 423 (2004). [2] T. Rödel, et al., Adv. Mater. 28, 1976 (2016).

Keywords: SrTiO3; redox-reaction; redox-reduction; two-dimensional electron gas; Laser reflectometry