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arXiv · 1211.6597

Ultrafast tuneable optical delay line based on indirect photonic transitions

Daryl M. Beggs·Isabella H. Rey·Tobias Kampfrath·Nir Rotenberg·L. Kuipers·Thomas F. Krauss
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Abstract

We introduce the concept of an indirect photonic transition and demonstrate its use in a dynamic delay line to alter the group velocity of an optical pulse. Operating on an ultrafast time scale, we show continuously tuneable delays of up to 20 ps, using a slow light photonic crystal waveguide only 300 $\mu$m in length. Our approach is flexible, in that individual pulses in a pulse stream can be controlled independently, which we demonstrate by operating on pulses separated by just 30 ps. The two-step indirect transition is demonstrated here with a 30% conversion efficiency.

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Daryl M. Beggs, Isabella H. Rey, Tobias Kampfrath, Nir Rotenberg, L. Kuipers, Thomas F. Krauss. 2012-11-28. Ultrafast tuneable optical delay line based on indirect photonic transitions. https://doi.org/10.1103/physrevlett.108.213901

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