Crafting oxide superlattices with efficient electron doping induced by interfacial charge transfer
Year: 2024
Type: article
Abstract: Charge doping represents one of the most successful approaches to regulating the properties of materials. Conventional chemical doping inevitably involves side effects from quenched disorder and is sometimes restricted by the choice of doping elements. In contrast, electrostatic doping makes it possible to inject carriers into materials in a clean manner; however, in materials with a high background carrier concentration, the working distance of electrostatic doping is rather limited due to the extremely short screening length. In this work, based on band-alignment considerations, we craft artificial superlattices of ${\mathrm{Sr}\mathrm{Ru}\mathrm{O}}_{3}/{\mathrm{Nd}\mathrm{Ni}\mathrm{O}}_{3}$ by intercalating a single-unit-cell charge-reservoir layer of ${\mathrm{Sr}\mathrm{Ru}\mathrm{O}}_{3}$ into a ${\mathrm{Nd}\mathrm{Ni}\mathrm{O}}_{3}$ matrix at varied periodicities. The designed electron transfer from ${\mathrm{Sr}\mathrm{Ru}\mathrm{O}}_{3}$ to ${\mathrm{Nd}\mathrm{Ni}\mathrm{O}}_{3}$ with accompanying orbital reconstruction is revealed by x-ray absorption spectroscopy. Such electron doping dramatically regulates the metal-insulator and antiferromagnetic transitions of ${\mathrm{Nd}\mathrm{Ni}\mathrm{O}}_{3}$. Moreover, bulklike E\ensuremath{'} antiferromagnetic order is observed in the superlattice with ${\mathrm{Nd}\mathrm{Ni}\mathrm{O}}_{3}$ layers down to a single unit cell, which is related to the interfacial ion exchange enhanced by the strong electron transfer in the ultrathin limit. Our work raises the prospect of customizing artificial oxide materials with efficient modulation doping, which may lead to emergent functionalities unattainable in natural crystals.
Source: Physical Review Applied
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4403980631