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Alternative approach to all-angle negative refraction in two-dimensional photonic crystals

Y. J. Huang·W. T. Lu·S. Sridhar
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Abstract

We show that with an appropriate surface modification, a slab of photonic crystal can be made to allow wave transmission within the band gap. Furthermore, negative refraction and all-angle-negative-refraction (AANR) can be achieved by this surface modification in frequency windows that were not realized before in two-dimensional photonic crystals [C. Luo et al, Phys. Rev. B 65, 201104 (2002)]. This approach to AANR leads to new applications in flat lens imaging. Previous flat lens using photonic crystals requires object-image distance u+v less than or equal to the lens thickness d, u+v d. Our approach can be used to design flat lens with u+v=sd with s>>1, thus being able to image large and/or far away objects. Our results are confirmed by FDTD simulations.

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Y. J. Huang, W. T. Lu, S. Sridhar. 2007-06-22. Alternative approach to all-angle negative refraction in two-dimensional photonic crystals. https://doi.org/10.1103/physreva.76.013824

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