Engineering of Ferroic Orders in Thin Films by Anionic Substitution. (7th October 2021)

• Record Type: Journal Article
• Authors: Garcia‐Castro, Andres Camilo; Ma, Yanjun; Romestan, Zachary; Bousquet, Eric; Cen, Cheng; Romero, Aldo H.
• Is Part Of: Advanced functional materials. Volume 32:Number 2(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-10-07
• Subjects: density‐functional theory -- ferroelectricity -- ferromagnetism -- multiferroics -- oxynitrides -- thin‐films; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202107135
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Multiferroics are a unique class of materials where magnetic and ferroelectric orders coexist. The research on multiferroics contributes significantly to the fundamental understanding of the strong correlations between different material degrees of freedom and provides an energy‐efficient route toward the electrical control of magnetism. While multiple ABO3 oxide perovskites are identified as being multiferroic, their magnetoelectric coupling strength is often weak, necessitating the material search in different compounds. Here, the observation of room‐temperature multiferroic orders in multi‐anion SrNbO3− x N x thin films is reported. In these samples, the multi‐anion state enables the room‐temperature ferromagnetic ordering of the Nb d‐electrons. Simultaneously, ferroelectric responses that originate from the structural symmetry breaking associated are found with both the off‐center displacements of Nb and the geometric displacements of Sr, depending on the relative O‐N arrangements within the Nb‐centered octahedra. The findings not only diversify the available multiferroic material pool but also demonstrate a new multiferroism design strategy via multi‐anion engineering. Abstract : Multiferroism induced in perovskite SrNbO3− x N x thin‐films: Ferroelectricity and ferromagnetism are tuned in niobium‐based oxynitride thin‐films under nitrogen content. In the study, experimental and theoretical efforts are combined synergistically to engineer, by anionic substitution in perovskite thin films, ferroic orders in an oxynitride prototype material. This particular X‐site exploration in perovskite‐like materials offers undiscovered design routes for revealing novel multifunctional materials.