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arXiv · 1112.4734

Exceptional Point Dynamics in Photonic Honeycomb Lattices with PT Symmetry

Hamidreza Ramezani·Tsampikos Kottos·Vassilios Kovanis·Demetrios N. Christodoulides
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Abstract

We theoretically investigate the flow of electromagnetic waves in complex honeycomb photonic lattices with local PT symmetries. Such PT structure is introduced via a judicious arrangement of gain or loss across the honeycomb lattice, characterized by a gain/loss parameter γ. We found a new class of conical diffraction phenomena where the formed cone is brighter and travels along the lattice with a transverse speed proportional to Sqrt (γ).

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Hamidreza Ramezani, Tsampikos Kottos, Vassilios Kovanis, Demetrios N. Christodoulides. 2011-12-20. Exceptional Point Dynamics in Photonic Honeycomb Lattices with PT Symmetry. https://doi.org/10.1103/physreva.85.013818

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