Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces

Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces

van Thiel, T.C. (TU Delft QN/Caviglia Lab; Kavli institute of nanoscience Delft)
Brzezicki, W. (Jagiellonian University; Polish Academy of Sciences)
Autieri, C. (Polish Academy of Sciences)
Hortensius, J.R. (TU Delft QN/Caviglia Lab; Kavli institute of nanoscience Delft)
Afanasiev, D. (TU Delft QN/Caviglia Lab; Kavli institute of nanoscience Delft)
Janssen, N. (Kavli institute of nanoscience Delft; Student TU Delft)
Groenendijk, D.J. (TU Delft QN/Caviglia Lab; Kavli institute of nanoscience Delft)
Van Aert, S. (Universiteit Antwerpen)
Caviglia, A. (TU Delft QN/Caviglia Lab; Kavli institute of nanoscience Delft)

2021

In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO3, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and LaAlO3, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO2/SrO interface configuration, leading to excess charge being pinned near the LaAlO3/SrRuO3 interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO3. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.

http://resolver.tudelft.nl/uuid:953895c6-5c5c-4983-968a-ff7ea658f17b

https://doi.org/10.1103/PhysRevLett.127.127202

0031-9007

Physical Review Letters, 127 (12)

Institutional Repository

journal article

© 2021 T.C. van Thiel, W. Brzezicki, C. Autieri, J.R. Hortensius, D. Afanasiev, N. Janssen, D.J. Groenendijk, S. Van Aert, A. Caviglia, More Authors