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arXiv · 1504.07473

Optically and Electrically Tunable Dirac Points and Zitterbewegung in Graphene-Based Photonic Superlattices

Hanying Deng·Fangwei Ye·Boris A. Malomed·Xianfeng Chen·Nicolae C. Panoiu
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Abstract

We demonstrate that graphene-based photonic superlattices provide a versatile platform for electrical and all-optical control of photonic beams with deep-subwavelength accuracy. Specifically, by inserting graphene sheets into periodic metallo-dielectric structures one can design optical superlattices that posses photonic Dirac points (DPs) at frequencies at which the spatial average of the permittivity of the superlattice, $\bar{ \varepsilon}$, vanishes. Similar to the well-known zero-$\bar{n}$ bandgaps, we show that these zero-$\bar{\varepsilon}$ DPs are highly robust against structural disorder. We also show that, by tuning the graphene permittivity via the optical Kerr effect or electrical doping, one can induce a spectral variation of the DP exceeding \SI{30}{\nano\meter}, at mid-IR and THz frequencies. The implications of this wide tunability for the photonic Zitterbewegung effect in a vicinity of the DP are explored too.

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Hanying Deng, Fangwei Ye, Boris A. Malomed, Xianfeng Chen, Nicolae C. Panoiu. 2015-04-28. Optically and Electrically Tunable Dirac Points and Zitterbewegung in Graphene-Based Photonic Superlattices. https://doi.org/10.1103/physrevb.91.201402

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