Sub-Sharvin conductance and incoherent shot-noise in graphene disks at magnetic field

Abstract

Highly-doped graphene samples show the conductance reduced and the shot-noise power enhanced compared to standard ballistic systems in two-dimensional electron gas. These features can be understood within a model assuming incoherent scattering of Dirac electrons between two interfaces separating the sample and the leads. Here we find, by adopting the above-mentioned model for the edge-free (Corbino) geometry and by means of the computer simulation of quantum transport, that another graphene-specific feature should be observable when the current flow through a doped disk is blocked by high magnetic field. In case the conductance drops to zero, the Fano factor approaches the value of $F\approx 0.56$, with a very weak dependence on the disk radii ratio. The role of finite source-drain voltages and the system behavior upon tuning the electrostatic potential barrier from a rectangular to parabolic shape are also discussed.

RevTeX, 15 pages, 7 figures

References in corpus (22)

• Universal Dynamic Conductivity and Quantized Visible Opacity of Suspended Graphene
• Chiral tunneling and the Klein paradox in graphene
• Doping graphene with metal contacts
• Quantum-limited shot noise in graphene
• Phase Coherent Transport of Charges in Graphene Quantum Billiard
• Shot Noise in Ballistic Graphene
• Bound states and magnetic field-induced valley splitting in gate-tunable graphene quantum dots
• Imaging Hydrodynamic Electrons Flowing Without Landauer-Sharvin Resistance
• Conformal mapping and shot noise in graphene
• Charge transport and shot noise in ballistic graphene sheet
• The transparency of graphene and other direct-gap two dimensional materials
• Evidence of Lifshitz transition in thermoelectric power of ultrahigh mobility bilayer graphene
• Wiedemann-Franz law in graphene
• Numerical Study of Universal Conductance Fluctuation in Three-dimensional Topological Semimetals
• Wiedemann-Franz law for massless Dirac fermions with implications for graphene
• Observation of flat bands in gated semiconductor artificial graphene
• Graphene disk in a solenoid magnetic potential: Aharonov-Bohm effect without a two-slit-like setup
• Magnetopumping current in graphene Corbino pump
• Klein tunneling through the trapezoidal potential barrier in graphene: conductance and shot noise
• Sub-Sharvin conductance and enhanced shot noise in doped graphene
• Thermoelectric properties of the Corbino disk in graphene
• Theory of the sub-Sharvin charge transport in graphene disks