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Resolving the wave-vector in negative refractive media: The sign of $\sqrt{Z}$

S. Anantha Ramakrishna·Olivier J. F. Martin
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Abstract

We address the general issue of resolving the wave-vector in complex electromagnetic media including negative refractive media. This requires us to make a physical choice for the sign of a square-root imposed merely by conditions of causality. By considering the analytic behaviour of the wave-vector in the complex plane, it is shown that there are a total of eight physically distinct cases in the four quadrants of two Riemann sheets.

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S. Anantha Ramakrishna, Olivier J. F. Martin. 2004-02-24. Resolving the wave-vector in negative refractive media: The sign of $\sqrt{Z}$. https://doi.org/10.1364/ol.30.002626

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