Charge transfer and metal–insulator transition in (CrO2)m/(TaO2)n superlattices. (21st September 2022)

• Record Type: Journal Article
• Authors: Shan, Wanfei; Luo, Weidong
• Is Part Of: Journal of physics. Volume 34:Number 38(2022)
• Publication Date: 2022-09-21
• Subjects: interfacial phenomena -- metal-to-insulator transition -- charge transfer; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac8133
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: Various interfacial emergent phenomena have been discovered in tunable nanoscale materials, especially in artificially designed epitaxial superlattices. In conjunction, the atomically fabricated superlattices have exhibited a plethora of exceptional properties compared to either bulk materials separately. Here, the (CrO2 ) m /(TaO2 ) n superlattices composed of two lattice-matched metallic metal oxides are constructed. With the help of first-principle density-functional theory calculations, a computational and theoretical study of (CrO2 ) m /(TaO2 ) n superlattices manifests the interfacial electronic properties in detail. The results suggest that emergent properties result from the charge transfer from the TaO2 to CrO2 layers. At two special ratios of 1 : 1 and 1 : 2 between m and n, the superlattices undergo metal-to-insulator transition. Additionally, the bands below the Fermi level become narrower with the increasing thickness of the CrO2 and TaO2 layers. The study reveals that the electronic reconstruction at the interface of two metallic materials can generate interesting physics, which points the direction for the manipulation of functionalities in artificial superlattices or heterostructures within a few atomic layers.