title: Dielectric screening in atomically thin boron nitride nanosheets.
abstract: Two-dimensional (2D) hexagonal boron nitride (BN) nanosheets are excellent dielectric substrate for graphene, molybdenum disulfide, and many other 2D nanomaterial-based electronic and photonic devices. To optimize the performance of these 2D devices, it is essential to understand the dielectric screening properties of BN nanosheets as a function of the thickness. Here, electric force microscopy along with theoretical calculations based on both state-of-the-art first-principles calculations with van der Waals interactions under consideration, and nonlinear Thomas-Fermi theory models are used to investigate the dielectric screening in high-quality BN nanosheets of different thicknesses. It is found that atomically thin BN nanosheets are less effective in electric field screening, but the screening capability of BN shows a relatively weak dependence on the layer thickness.
authors.affiliation: Institute for Frontier Materials, Deakin University , Geelong Waurn Ponds Campus, Waurn Ponds, Victoria 3216, Australia.
authors.forename: Lu Hua
authors.initials: LH
authors.lastname: Li
authors.forename: Elton J G
authors.initials: EJ
authors.lastname: Santos
authors.forename: Tan
authors.initials: T
authors.lastname: Xing
authors.forename: Emmanuele
authors.initials: E
authors.lastname: Cappelluti
authors.forename: Rafael
authors.initials: R
authors.lastname: Roldán
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Kenji
authors.initials: K
authors.lastname: Watanabe
authors.forename: Takashi
authors.initials: T
authors.lastname: Taniguchi
keywords: boron nitride nanosheets; electric field screening; electric force microscopy (EFM); first-principles calculations; nonlinear Thomas−Fermi theory