中国物理B ›› 2015, Vol. 24 ›› Issue (8): 87101-087101.doi: 10.1088/1674-1056/24/8/087101

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Low-temperature charged impurity scattering-limited conductivity in relatively high doped bilayer graphene

胡波   

  1. State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • 收稿日期:2014-09-09 修回日期:2015-03-20 出版日期:2015-08-05 发布日期:2015-08-05

Low-temperature charged impurity scattering-limited conductivity in relatively high doped bilayer graphene

Hu Bo (胡波)   

  1. State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • Received:2014-09-09 Revised:2015-03-20 Online:2015-08-05 Published:2015-08-05
  • Contact: Hu Bo E-mail:hubo2011@semi.ac.cn

摘要: Based on semiclassical Boltzamnn transport theory in random phase approximation, we develop a theoretical model to investigate low-temperature carrier transport properties in relatively high doped bilayer graphene. In the presence of both electron–hole puddles and band gap induced by charged impurities, we calculate low-temperature charged impurity scattering-limited conductivity in relatively high doped bilayer graphene. Our calculated conductivity results are in excellent agreement with published experimental data in all compensated gate voltage regime of study by using potential fluctuation parameter as only one free fitting parameter, indicating that both electron–hole puddles and band gap induced by charged impurities play an important role in carrier transport. More importantly, we also find that the conductivity not only depends strongly on the total charged impurity density, but also on the top layer charged impurity density, which is different from that obtained by neglecting the opening of band gap, especially for bilayer graphene with high top layer charged impurity density.

关键词: bilayer graphene, tunable band gap, electron–, hole puddles, charged impurity scattering

Abstract: Based on semiclassical Boltzamnn transport theory in random phase approximation, we develop a theoretical model to investigate low-temperature carrier transport properties in relatively high doped bilayer graphene. In the presence of both electron–hole puddles and band gap induced by charged impurities, we calculate low-temperature charged impurity scattering-limited conductivity in relatively high doped bilayer graphene. Our calculated conductivity results are in excellent agreement with published experimental data in all compensated gate voltage regime of study by using potential fluctuation parameter as only one free fitting parameter, indicating that both electron–hole puddles and band gap induced by charged impurities play an important role in carrier transport. More importantly, we also find that the conductivity not only depends strongly on the total charged impurity density, but also on the top layer charged impurity density, which is different from that obtained by neglecting the opening of band gap, especially for bilayer graphene with high top layer charged impurity density.

Key words: bilayer graphene, tunable band gap, electron–hole puddles, charged impurity scattering

中图分类号:  (Electron density of states and band structure of crystalline solids)

  • 71.20.-b
72.20.Dp (General theory, scattering mechanisms) 72.20.Fr (Low-field transport and mobility; piezoresistance)