Dielectric Screening in Atomically Thin Boron Nitride Nanosheets

详细信息    查看全文

• 作者：Lu Hua Li ; Elton J. G. Santos ; Tan Xing ; Emmanuele Cappelluti ; Rafael Rold谩n ; Ying Chen ; Kenji Watanabe ; Takashi Taniguchi
• 刊名：Nano Letters
• 出版年：2015
• 出版时间：January 14, 2015
• 年：2015
• 卷：15
• 期：1
• 页码：218-223
• 全文大小：391K
• ISSN：1530-6992

文摘

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鈥揊ermi 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.