%0 Journal Article
%T Optically and Electrically Tunable Dirac Points and Zitterbewegung in Graphene-Based Photonic Superlattices
%A Hanying Deng
%A Fangwei Ye
%A Boris A. Malomed
%A Xianfeng Chen
%A Nicolae C. Panoiu
%J Physics
%D 2015
%I arXiv
%R 10.1103/PhysRevB.91.201402
%X 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.
%U http://arxiv.org/abs/1504.07473v1