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arXiv · 1312.7601

Conditions for Conductance Quantization in Mesoscopic Dirac Systems on the Examples of Graphene Nanoconstrictions

Grzegorz Rut·Adam Rycerz
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Abstract

Ballistic transport through an impurity-free section of the Corbino disk in graphene is investigated by means of the Landauer-B\"{u}ttiker formalism in the mesoscopic limit. In the linear-responce regime the conductance is quantized in steps close to integer multiples of $4e^{2}/h$, yet Fabry-Perot oscillations are strongly suppressed. The quantization arises for small opening angles $\theta\lesssim\pi/3$ and large radii ratios $R_2/R_1\gtrsim{}10$. We find that the condition for emergence of the $n$-th conductance step can be written as $\sqrt{n}\theta/\pi\ll{}1$. A brief comparison with the conductance spectra of graphene nanoribbons with parallel edges is also provided.

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Grzegorz Rut, Adam Rycerz. 2013-12-29. Conditions for Conductance Quantization in Mesoscopic Dirac Systems on the Examples of Graphene Nanoconstrictions. https://doi.org/10.12693/aphyspola.126.a-114

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