Abstract
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 , an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and , a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp interface configuration, leading to excess charge being pinned near the 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 . Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces.
- Received 11 June 2021
- Accepted 21 July 2021
- Corrected 10 March 2022
DOI:https://doi.org/10.1103/PhysRevLett.127.127202
© 2021 American Physical Society
Physics Subject Headings (PhySH)
Corrections
10 March 2022
Correction: The previously published Fig. 2(c) contained errors in the labels of the two topmost curves and was replaced.