Electron-electron interactions in monolayer graphene quantum capacitors

作     者：Xiaolong Chen Lin Wang Wei Li Yang Wang Zefei Wu Mingwei Zhang Yu Han Yuheng He Ning Wang 

作者机构：Department of Physics and the William Mong Institute of Nano Science and Technology Hong Kong University of Science andTechnology Hong Kong S.A.R. China 

出 版 物：《Nano Research》 (纳米研究（英文版）)

年 卷 期：2013年第6卷第8期

页      面：619-626页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：support from the Research Grants Council of Hong Kong support by the Raith–Hong Kong University of Science and Technology (HKUST) Nanotechnology Laboratory for the electronbeam lithography facility at Material Characterization and Preparations Facility (MCPF) 

主　　题：graphene e-e interaction inverse compressibility quantum capacitance charge fluctuation electron-hole puddles 

摘      要：We demonstrate the effects of electron-electron （e-e） interactions in monolayer graphene quantum capacitors. Ultrathin yttrium oxide showed excellent per-formance as the dielectric layer in top-gate device geometry. The structure and dielectric constant of the yttrium oxide layers have been carefully studied. The inverse compressibility retrieved from the quantum capacitance agreed fairly well with the theoretical predictions for the e--e interactions in monolayer graphene at different temperatures. We found that electron-hole puddles played a significant role in the low-density carrier region in graphene. By considering the temperature-dependent charge fluctuation, we established a model to explain the round-off effect originating from the e-e interactions in monolayer graphene near the Dirac point.