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arXiv · 1003.2072

Current-voltage characteristics of graphene devices: interplay between Zener-Klein tunneling and defects

Niels Vandecasteele·Amelia Barreiro·Michele Lazzeri·Adrian Bachtold·Francesco Mauri
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Abstract

We report a theoretical/experimental study of current-voltage characteristics (I-V) of graphene devices near the Dirac point. The I-V can be described by a power law (I \propto V^\alpha, with 1< \alpha <= 1.5). The exponent is higher when the mobility is lower. This superlinear I-V is interpreted in terms of the interplay between Zener-Klein transport, that is tunneling between different energy bands, and defect scattering. Surprisingly, the Zener-Klein tunneling is made visible by the presence of defects.

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Niels Vandecasteele, Amelia Barreiro, Michele Lazzeri, Adrian Bachtold, Francesco Mauri. 2010-03-10. Current-voltage characteristics of graphene devices: interplay between Zener-Klein tunneling and defects. https://doi.org/10.1103/physrevb.82.045416

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