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Title: Effect of impurity doping in gapped bilayer graphene

Abstract

Impurity doping plays a pivotal role in semiconductor electronics. We study the doping effect in a two-dimensional semiconductor, gapped bilayer graphene. By employing in situ deposition of calcium on the bilayer graphene, dopants are controllably introduced. Low temperature transport results show a variable range hopping conduction near the charge neutrality point persisting up to 50 K, providing evidence for the impurity levels inside the gap. Our experiment confirms a predicted peculiar effect in the gapped bilayer graphene, i.e., formation of in-gap states even if the bare impurity level lies in the conduction band. The result provides perspective on the effect of doping and impurity levels in semiconducting bilayer graphene.

Authors:
; ; ; ; ;  [1]
  1. State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Peking University, Beijing 100871, China and Collaborative Innovation Center of Quantum Matter, Beijing 100871 (China)
Publication Date:
OSTI Identifier:
22485944
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 16; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CALCIUM; DEPOSITION; DOPED MATERIALS; GRAPHENE; IMPURITIES; LAYERS; SEMICONDUCTOR MATERIALS; TWO-DIMENSIONAL SYSTEMS

Citation Formats

Han, Qi, Yan, Baoming, Jia, Zhenzhao, Niu, Jingjing, Yu, Dapeng, and Wu, Xiaosong, E-mail: xswu@pku.edu.cn. Effect of impurity doping in gapped bilayer graphene. United States: N. p., 2015. Web. doi:10.1063/1.4934489.
Han, Qi, Yan, Baoming, Jia, Zhenzhao, Niu, Jingjing, Yu, Dapeng, & Wu, Xiaosong, E-mail: xswu@pku.edu.cn. Effect of impurity doping in gapped bilayer graphene. United States. doi:10.1063/1.4934489.
Han, Qi, Yan, Baoming, Jia, Zhenzhao, Niu, Jingjing, Yu, Dapeng, and Wu, Xiaosong, E-mail: xswu@pku.edu.cn. Mon . "Effect of impurity doping in gapped bilayer graphene". United States. doi:10.1063/1.4934489.
@article{osti_22485944,
title = {Effect of impurity doping in gapped bilayer graphene},
author = {Han, Qi and Yan, Baoming and Jia, Zhenzhao and Niu, Jingjing and Yu, Dapeng and Wu, Xiaosong, E-mail: xswu@pku.edu.cn},
abstractNote = {Impurity doping plays a pivotal role in semiconductor electronics. We study the doping effect in a two-dimensional semiconductor, gapped bilayer graphene. By employing in situ deposition of calcium on the bilayer graphene, dopants are controllably introduced. Low temperature transport results show a variable range hopping conduction near the charge neutrality point persisting up to 50 K, providing evidence for the impurity levels inside the gap. Our experiment confirms a predicted peculiar effect in the gapped bilayer graphene, i.e., formation of in-gap states even if the bare impurity level lies in the conduction band. The result provides perspective on the effect of doping and impurity levels in semiconducting bilayer graphene.},
doi = {10.1063/1.4934489},
journal = {Applied Physics Letters},
number = 16,
volume = 107,
place = {United States},
year = {Mon Oct 19 00:00:00 EDT 2015},
month = {Mon Oct 19 00:00:00 EDT 2015}
}
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