2006/02/07 by D. N. Sheng, Li Sheng, L. Sheng +2 · 3 citations
Materials Science · Physics and Astronomy · #Condensed matter physics #Electronic band structure #Graphene #Graphene research and applications #Landau quantization #Magnetic field #Phase (matter) #Phase diagram #Physics #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.73.233406
published as Phys. Rev. B 73, 233406 (2006). · 4 pages, 4 figures
arxiv created 2006/02/07 · openalex publication_date 2006/06/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We numerically study the quantum Hall effect (QHE) in graphene based on a lattice model in the presence of disorder. Two distinct QHE regimes are identified in the energy band with unconventional ``half-integer'' QHE appearing near the band center, in agreement with the experimental observation. A topological invariant Chern number description provides a consistent understanding of the peculiar behavior of the two QHE regimes in the energy band. The phase diagram for the unconventional QHE is obtained where the destruction of the Hall plateaus at strong disorder is through the float-up of extended levels towards the band center. An insulating phase emerges between \ensuremathν=\ifmmode±\else\textpm\fi2 QHE plateaus at the band center in weak disorder region, which may explain the experimentally observed resistance discontinuity near zero gate voltage.