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Room-temperature ballistic transport in narrow graphene strips

D. Gunlycke·H. M. Lawler·C. T. White
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Abstract

We investigate electron-phonon couplings, scattering rates, and mean free paths in zigzag-edge graphene strips with widths of the order of 10 nm. Our calculations for these graphene nanostrips show both the expected similarity with single-wall carbon nanotubes (SWNTs) and the suppression of the electron-phonon scattering due to a Dirichlet boundary condition that prohibits one major backscattering channel present in SWNTs. Low-energy acoustic phonon scattering is exponentially small at room temperature due to the large phonon wave vector required for backscattering. We find within our model that the electron-phonon mean free path is proportional to the width of the nanostrip and is approximately 70 $μ$m for an 11-nm-wide nanostrip.

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D. Gunlycke, H. M. Lawler, C. T. White. 2007-02-21. Room-temperature ballistic transport in narrow graphene strips. https://doi.org/10.1103/physrevb.75.085418

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