Dresden 2026 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

MA: Fachverband Magnetismus

MA 41: Focus Session: Nickelate Superconductivity: Insights into Unconventional Pairing and Correlation Effects II (joint session TT/DS/MA)

MA 41.3: Talk

Thursday, March 12, 2026, 10:00–10:15, HSZ/0003

A photoinduced two-dimensional electron gas (2DEG) at infinite-layer nickelate/strontium titanate interfaces — •D. Sanchez-Manzano¹, G. Krieger², A. Raji³, B. Geisler⁴, V. Humbert¹, H. Jaffres¹, J. Santamaria⁵, R. Pentcheva⁴, A. Glotter³, D. Preziosi², and Javier E. Villegas¹ — ¹Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, France. — ²Institute of Physics and Chemistry of Materials of Strasbourg, CNRS, University of Strasbourg, France. — ³Laboratoire de Physique de Solides, CNRS, Université Paris-Saclay, France. — ⁴Department of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Germany — ⁵6Departamento de Física de Materiales, Universidad Complutense de Madrid, Spain

We demonstrate, through experiments (transport, electron microscopy & spectroscopy) and density functional theory (DFT), that a high-mobility 2DEG can be optically switched on and off at an oxide interface where such a state does not naturally exist [1]. We show that near-ultraviolet light instantly creates a volatile 2DEG at the interface between SrTiO₃ (a band insulator) and infinite-layer NdNiO₂ (a poor metal), resulting in a conductivity increase of up to five orders of magnitude. This stems from structural and electronic reconstructions that, along with a built-in interfacial electric field, facilitate the Ti-3d band occupation by photogenerated carriers. These findings open venues for engineering photoconductance in strongly correlated systems.
[1] Sanchez-Manzano et al., Nat. Mater. (2025).
https://doi.org/10.1038/s41563-025-02363-y

Keywords: complex-oxide heterostructures; nickelates; strong correlations; STEM; two-dimensional electron gas