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arXiv · 1804.01541

Faster light with competing absorption and gain

Jon D. Swaim·Ryan T. Glasser
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Abstract

We experimentally investigate the propagation of optical pulses through a fast-light medium with competing absorption and gain. The combination of strong absorption and optical amplification in a potassium-based four-wave mixing process results in pulse peak advancements up to $88\%$ of the input pulse width, more than $35 \times$ that which is achievable without competing absorption. We show that the enhancement occurs even when the total gain of the four-wave mixer is unity, thereby rendering the medium transparent. By varying the pulse width, we observe a transition between fast and slow light, and show that fast light is optimized for large pulse widths.

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Jon D. Swaim, Ryan T. Glasser. 2018-04-04. Faster light with competing absorption and gain. https://doi.org/10.1364/oe.26.010643

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