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arXiv · 1204.0500

Enabling single-mode behavior over large areas with photonic Dirac cones

J. Bravo-Abad·J. D. Joannopoulos·M. Soljacic
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Abstract

Many of graphene's unique electronic properties emerge from its Dirac-like electronic energy spectrum. Similarly, it is expected that a nanophotonic system featuring Dirac dispersion will open a path to a number of important research avenues. To date, however, all proposed realizations of a photonic analog of graphene lack fully omnidirectional out-of-plane light confinement, which has prevented creating truly realistic implementations of this class of systems. Here we report on a novel route to achieve all-dielectric three-dimensional photonic materials featuring Dirac-like dispersion in a quasi-two-dimensional system. We further discuss how this finding could enable a dramatic enhancement of the spontaneous emission coupling efficiency (the \beta-factor) over large areas, defying the common wisdom that the \beta-factor degrades rapidly as the size of the system increases. These results might enable general new classes of large-area ultralow-threshold lasers, single-photon sources, quantum information processing devices and energy harvesting systems.

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J. Bravo-Abad, J. D. Joannopoulos, M. Soljacic. 2012-04-02. Enabling single-mode behavior over large areas with photonic Dirac cones. https://doi.org/10.1073/pnas.1207335109

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