2014/05/31 by Grzegorz Rut, Adam Rycerz · 1 citation
Materials Science · Physics and Astronomy · #Bilayer #Bilayer graphene #Conductance #Dirac (video compression format) #Electron #Graphene research and applications #Landau quantization #Monolayer #Oscillation (cell signaling) #Quantum and electron transport phenomena #Quantum tunnelling #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1088/0953-8984/26/48/485301
published as J. Phys.: Condens. Matter 26, 485301 (2014) · Typos corrected; acknowledgment added. RevTeX, 13 pages, 7 figures
arxiv created 2014/10/03 · openalex publication_date 2014/11/04 · arxiv updated 2014/11/07 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Quantum transport through an impurity-free Corbino disk in bilayer graphene is investigated analytically, using the mode-matching method to give an effective Dirac equation, in the presence of uniform magnetic fields. Similarly as in the monolayer case (see Rycerz 2010 Phys. Rev. B 81 121404; Katsnelson 2010 Europhys. Lett. 89 17001), conductance at the Dirac point shows oscillations with the flux piercing the disk area ΦD characterized by the period Φ(0) = 2 (h/e) ln(R(o)/R(i)), where R(o)(R(i)) is the outer (inner) disk radius. The oscillation magnitude depends either on the radii ratio or on the physical disk size, with the condition for maximal oscillations being R(o)/R(i) ≃ [ Rit⊥/(2ℏvF) ](4/p) (for R(o)/R(i) ≫ 1), where t⊥ is the interlayer hopping integral, vF is the Fermi velocity in graphene, and p is an even integer. Odd-integer values of p correspond to vanishing oscillations for the normal Corbino setup, or to oscillation frequency doubling for the Andreev-Corbino setup. At higher Landau levels, magnetoconductance behaves almost identically in the monolayer and bilayer cases. A brief comparison with the Corbino disk in a two-dimensional electron gas is also provided in order to illustrate the role of chiral tunneling in graphene.