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arXiv · 1401.6241

Photo-oxidative tuning of individual and coupled GaAs photonic crystal cavities

Alexander Y. Piggott·Konstantinos G. Lagoudakis·Tomas Sarmiento·Michal Bajcsy·Gary Shambat·Jelena Vučković
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Abstract

We demonstrate a new photo-induced oxidation technique for tuning GaAs photonic crystal cavities using a $390~\mathrm{nm}$ pulsed laser with an average power of $10~\mathrm{μW}$. The laser oxidizes a small $\left(\sim 500~\mathrm{nm}\right)$ diameter spot, reducing the local index of refraction and blueshifting the cavity. The tuning progress can be actively monitored in real time. We also demonstrate tuning an individual cavity within a pair of proximity-coupled cavities, showing that this method can be used to correct undesired frequency shifts caused by fabrication imperfections in cavity arrays.

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Alexander Y. Piggott, Konstantinos G. Lagoudakis, Tomas Sarmiento, Michal Bajcsy, Gary Shambat, Jelena Vučković. 2014-01-30. Photo-oxidative tuning of individual and coupled GaAs photonic crystal cavities. https://doi.org/10.1364/oe.22.015017

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