Regensburg 2010 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 22: Graphene 2 (Joint Session with TT)

HL 22.1: Vortrag

Dienstag, 23. März 2010, 09:30–09:45, H21

Relativistic quantum Corbino effect in graphene — •Adam Rycerz — Institut für Theoretische Physik, Universität Regensburg, D–93040, Germany — Marian Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, PL–30059 Kraków, Poland

Electron transport through the Corbino disk in graphene is studied in the presence of uniform magnetic fields. At the Dirac point, we observe conductance oscillations with the flux piercing the disk area Φ_d, characterized by the period Φ₀=(2h/e)ln(R_o/R_i), where R_o (R_i) is the outer (inner) disk radius. The oscillations magnitude increase with the radii ratio and exceed 10% of the average conductance for R_o/R_i 5 in the case of the normal Corbino setup, or for R_o/R_i 2.2 in the case of the Andreev-Corbino setup. At a finite but weak doping, the oscillations still appear in a limited range of |Φ_d|Φ_d^max, away from which the conductance is strongly suppressed. At large dopings and weak fields we identify the crossover to a ballistic transport regime.

[1] A. Rycerz, arXiv:0909.3018 (unpublished).