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Electromagnetic field induced suppression of transport through $n$-$p$ junctions in graphene

M. V. Fistul·K. B. Efetov
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Abstract

We study quasi-particle transmission through an $n $-$p$ junction in a graphene irradiated by an electromagnetic field (EF). In the absence of EF the electronic spectrum of undoped graphene is gapless, and one may expect the perfect transmission of quasi-particles flowing perpendicular to the junction. We demonstrate that the resonant interaction of propagating quasi-particles with the component of EF parallel to the junction induces a \textit{non-equilibrium dynamic gap} $(2Δ_R)$ between electron and hole bands in the quasi-particle spectrum of graphene. In this case the strongly suppressed quasi-particle transmission is only possible due to interband tunnelling. The effect may be used for controlling transport properties of diverse structures in graphene, like, e.g., $n$-$p$-$n$ transistors, single electron transistors, quantum dots, etc., by variation of the intensity $S$ and frequency $ω$ of the external radiation.

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M. V. Fistul, K. B. Efetov. 2007-03-16. Electromagnetic field induced suppression of transport through $n$-$p$ junctions in graphene. https://doi.org/10.1103/physrevlett.98.256803

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