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Conductance quantization in mesoscopic graphene

N. M. R. Peres·A. H. Castro Neto·F. Guinea
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Abstract

Using a generalized Landauer approach we study the non-linear transport in mesoscopic graphene with zig-zag and armchair edges. We find that for clean systems, the low-bias low-temperature conductance, G, of an armchair edge system in quantized as G/t=4 n e^2/h, whereas for a zig-zag edge the quantization changes to G/t t=4(n+1/2)e^2/h, where t is the transmission probability and n is an integer. We also study the effects of a non-zero bias, temperature, and magnetic field on the conductance. The magnetic field dependence of the quantization plateaus in these systems is somewhat different from the one found in the two-dimensional electron gas due to a different Landau level quantization.

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N. M. R. Peres, A. H. Castro Neto, F. Guinea. 2006-05-14. Conductance quantization in mesoscopic graphene. https://doi.org/10.1103/physrevb.73.195411

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