Ionic Gating for Tuning Electronic and Magnetic Properties

The energy-efficient manipulation of the properties of functional materials is of great interest from both a scientific and an applied perspective. The application of electric fields is one of the most widely used methods to induce significant changes in the properties of materials, such as their structural, transport, magnetic, and optical properties. This article presents an overview of recent research on the manipulation of the electronic and magnetic properties of various material systems via electrolyte-based ionic gating. Oxides, magnetic thin-film heterostructures, and van der Waals 2D layers are discussed as exemplary systems. The detailed mechanisms through which ionic gating can induce significant changes in material properties, including their crystal and electronic structure and their electrical, optical, and magnetic properties, are summarized. Current and potential future functional devices enabled by such ionic control mechanisms are also briefly summarized, especially with respect to the emerging field of neuromorphic computing. Finally, a brief outlook and some key challenges are presented. Expected final online publication date for the Annual Review of Materials Research, Volume 53 is July 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.