Sub-Sharvin Conductance and Incoherent Shot-Noise in Graphene Disks at Magnetic Field.
| Autor: | Rycerz A; Institute for Theoretical Physics, Jagiellonian University, Łojasiewicza 11, PL-30348 Kraków, Poland., Rycerz K; Faculty of Computer Science, AGH University of Krakow, al. Mickiewicza 30, PL-30059 Kraków, Poland., Witkowski P; Institute for Theoretical Physics, Jagiellonian University, Łojasiewicza 11, PL-30348 Kraków, Poland. |
|---|---|
| Jazyk: | angličtina |
| Zdroj: | Materials (Basel, Switzerland) [Materials (Basel)] 2024 Jun 21; Vol. 17 (13). Date of Electronic Publication: 2024 Jun 21. |
| DOI: | 10.3390/ma17133067 |
| Abstrakt: | Highly doped graphene samples show reduced conductance and enhanced shot-noise power compared with standard ballistic systems in two-dimensional electron gas. These features can be understood within a model that assumes incoherent scattering of Dirac electrons between two interfaces separating the sample and the leads. Here we find, by adopting the above model for the edge-free (Corbino) geometry and by computer simulation of quantum transport, that another graphene-specific feature should be observable when the current flow through a doped disk is blocked by a strong magnetic field. When the conductance drops to zero, the Fano factor approaches the value of F≈0.56, with a very weak dependence on the ratio of the disk radii. The role of finite source-drain voltages and the system behavior when the electrostatic potential barrier is tuned from a rectangular to a parabolic shape are also discussed. |
| Databáze: | MEDLINE |
| Externí odkaz: |
|