Prediction of intrinsic two-dimensional ferroelectrics in In<sub>2</sub>Se<sub>3</sub> and other III<sub>2</sub>-VI<sub>3</sub> van der Waals materials.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28387225.
- Also identified by DOI 10.1038/ncomms14956 and PMC identifier 5385629.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Interest in two-dimensional (2D) van der Waals materials has grown rapidly across multiple scientific and engineering disciplines in recent years. However, ferroelectricity, the presence of a spontaneous electric polarization, which is important in many practical applications, has rarely been reported in such materials so far. Here we employ first-principles calculations to discover a branch of the 2D materials family, based on In<sub>2</sub>Se<sub>3</sub> and other III<sub>2</sub>-VI<sub>3</sub> van der Waals materials, that exhibits room-temperature ferroelectricity with reversible spontaneous electric polarization in both out-of-plane and in-plane orientations. The device potential of these 2D ferroelectric materials is further demonstrated using the examples of van der Waals heterostructures of In<sub>2</sub>Se<sub>3</sub>/graphene, exhibiting a tunable Schottky barrier, and In<sub>2</sub>Se<sub>3</sub>/WSe<sub>2</sub>, showing a significant band gap reduction in the combined system. These findings promise to substantially broaden the tunability of van der Waals heterostructures for a wide range of applications.