Prediction of nonlayered oxide monolayers as flexible high-κ dielectrics with negative Poisson's ratios.

ABSTRACT: During the last two decades, two-dimensional (2D) materials have been the focus of condensed matter physics and material science due to their promising fundamental properties and (opto-)electronic applications. However, high-κ 2D dielectrics that can be integrated within 2D devices are often missing. Here, we propose nonlayered oxide monolayers with calculated exfoliation energy as low as 0.39 J/m² stemming from the ionic feature of the metal oxide bonds. We predict 51 easily or potentially exfoliable oxide monolayers, including metals and insulators/semiconductors, with intriguing physical properties such as ultra-high κ values, negative Poisson's ratios and large valley spin splitting. Among them, the most promising dielectric, GeO₂, exhibits an auxetic effect, a κ

SUBMITTER: Hu Y 

PROVIDER: S-EPMC10582060 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature