• 文献标题:   Percolation transitions in bilayer graphene encapsulated by hexagonal boron nitride
  • 文献类型:   Article
  • 作  者:   COBALEDA C, PEZZINI S, RODRIGUEZ A, DIEZ E, BELLANI V
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   CNR
  • 被引频次:   4
  • DOI:   10.1103/PhysRevB.90.161408
  • 出版年:   2014

▎ 摘  要

We studied the plateau-plateau transitions that characterize the electrical transport in the quantum Hall regime in a high mobility bilayer graphene flake encapsulated by hexagonal boron nitride at magnetic fields up to 9 T and temperatures above 300 mK. We measured independently the exponent kappa of the temperature-induced transition broadening, the critical exponent gamma of the localization length, and the exponent p ruling the temperature scaling of the coherence length, finding consistency with the relation gamma = p/2 kappa The observed value of kappa = 0.30(0.28,0.32) deviates from that of the quantum Hall critical point. The obtained gamma = 1.25(0.96,1.54) questions the validity of a pure Anderson transition, and reveals percolation as the underlying driving mechanism.