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arXiv · 0906.4491

Non-Euclidean cloaking for light waves

Tomas Tyc·Huanyang Chen·Che Ting Chan·Ulf Leonhardt
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Abstract

Non-Euclidean geometry combined with transformation optics has recently led to the proposal of an invisibility cloak that avoids optical singularities and therefore can work, in principle, in a broad band of the spectrum [U. Leonhardt and T. Tyc, Science 323, 110 (2009)]. Such a cloak is perfect in the limit of geometrical optics, but not in wave optics. Here we analyze, both analytically and numerically, full wave propagation in non-Euclidean cloaking. We show that the cloaking device performs remarkably well even in a regime beyond geometrical optics where the device is comparable in size with the wavelength. In particular, the cloak is nearly perfect for a spectrum of frequencies that are related to spherical harmonics. We also show that for increasing wavenumber the device works increasingly better, approaching perfect behavior in the limit of geometrical optics.

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Tomas Tyc, Huanyang Chen, Che Ting Chan, Ulf Leonhardt. 2009-06-24. Non-Euclidean cloaking for light waves. https://doi.org/10.1109/jstqe.2009.2032514

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