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arXiv · 0805.4240

A common model for superluminal propagation in absorbing atomic media and lossy metastructures

P. Chamorro-Posada·F. J. Fraile-Pelaez
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Abstract

We analyse the superluminal propagation of narrow-band pulses at resonances in dissipative media. The output waveform is an attenuated, undistorted, time-advanced version of the input which can be interpreted as the result of the interference of two scaled replicas of the input having a positive relative delay. The proposed analysis applies both to the propagation in a passive bulk medium at an electronic resonance and in a dielectric waveguide coupled to a lossy micro-ring resonator. This latter case provides a clear insight of the underlying physical phenomena.

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P. Chamorro-Posada, F. J. Fraile-Pelaez. 2008-05-29. A common model for superluminal propagation in absorbing atomic media and lossy metastructures. https://arxiv.org/abs/0805.4240

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