Charge localization at the interface between La1-xSrxMnO3 and the infinite layers cuprate CaCuO2

TL;DR

This study investigates charge localization at the interface of La1-xSrxMnO3 and CaCuO2 superlattices, revealing orbital reconstruction and hole localization that influence their electronic and magnetic properties.

Contribution

It provides direct evidence of orbital hybridization and charge localization mechanisms at the interface, advancing understanding of oxide heterostructure interfaces.

Findings

Orbital reconstruction occurs at the interface due to Cu-Mn hybridization.

Holes are localized at the interface, preventing charge transfer to CaCuO2.

Charge transfer to the manganite layer affects magnetotransport properties.

Abstract

(CaCuO2)m/(La0.7Sr0.3MnO3)n superlattices, consisting of the infinite layers cuprate CaCuO2 and the optimally doped manganite La1-xSrxMnO3, were grown by pulsed laser deposition. The transport properties are dominated by the manganite block. X-Ray Absorption spectroscopy measurements show a clear evidence of an orbital reconstruction at the interface, ascribed to the hybridization between the Cu 3d3z2-r2 and the Mn 3d3z2-r2 orbitals via interface apical oxygen ions. Such a mechanism localizes holes at the interfaces, thus preventing charge transfer to the CaCuO2 block. Some charge (holes) transfer occurs toward the La0.7Sr0.3MnO3 block in strongly oxidized superlattices, contributing to the suppression of the magnetotransport properties.