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Graphene quantum point contact transistor for DNA sensing.

ABSTRACT: By using the nonequilibrium Green's function technique, we show that the shape of the edge, the carrier concentration, and the position and size of a nanopore in graphene nanoribbons can strongly affect its electronic conductance as well as its sensitivity to external charges. This technique, combined with a self-consistent Poisson-Boltzmann formalism to account for ion charge screening in solution, is able to detect the rotational and positional conformation of a DNA strand inside the nanopore. In particular, we show that a graphene membrane with quantum point contact geometry exhibits greater electrical sensitivity than a uniform armchair geometry provided that the carrier concentration is tuned to enhance charge detection. We propose a membrane design that contains an electrical gate in a configuration similar to a field-effect transistor for a graphene-based DNA sensing device.

SUBMITTER: Girdhar A

PROVIDER: S-EPMC3801026 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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Graphene quantum point contact transistor for DNA sensing.

Girdhar Anuj A Sathe Chaitanya C Schulten Klaus K Leburton Jean-Pierre JP

Proceedings of the National Academy of Sciences of the United States of America 20130930 42

By using the nonequilibrium Green's function technique, we show that the shape of the edge, the carrier concentration, and the position and size of a nanopore in graphene nanoribbons can strongly affect its electronic conductance as well as its sensitivity to external charges. This technique, combined with a self-consistent Poisson-Boltzmann formalism to account for ion charge screening in solution, is able to detect the rotational and positional conformation of a DNA strand inside the nanopore. ...[more]

PMID: 24082108

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