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arXiv · 1506.02436

An angle on invisibility

H. F. Jones·M. Kulishov
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Abstract

The $PT$-symmetric optical grating with index profile $e^{i\beta z}$ has been shown to have the interesting property of being essentially invisible for light incident from one side, while possessing greatly enhanced reflection at a particular wavelength for light incident from the other side. We extend a previous analysis of this grating to obtain an analytic solution for the case when the grating is embedded on a substrate, with different refractive indices on either side. We also generalize the previous case of normal incidence to incidence at an arbitrary angle. In that case the enhanced reflection occurs at a particular angle of incidence for a given wavelength. Finally we discuss how the grating may be used to give lasing.

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H. F. Jones, M. Kulishov. 2015-06-08. An angle on invisibility. https://arxiv.org/abs/1506.02436

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