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arXiv · 0809.3855

Slow-light enhanced light-matter interactions with applications to gas sensing

K. H. Jensen·M. N. Alam·B. Scherer·A. Lambrecht·N. A. Mortensen
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Abstract

Optical gas detection in microsystems is limited by the short micron scale optical path length available. Recently, the concept of slow-light enhanced absorption has been proposed as a route to compensate for the short path length in miniaturized absorption cells. We extend the previous perturbation theory to the case of a Bragg stack infiltrated by a spectrally strongly dispersive gas with a narrow and distinct absorption peak. We show that considerable signal enhancement is possible. As an example, we consider a Bragg stack consisting of PMMA infiltrated by O2. Here, the required optical path length for visible to near-infrared detection (~760 nm) can be reduced by at least a factor of 10^2, making a path length of 1 mm feasible. By using this technique, optical gas detection can potentially be made possible in microsystems.

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K. H. Jensen, M. N. Alam, B. Scherer, A. Lambrecht, N. A. Mortensen. 2008-09-23. Slow-light enhanced light-matter interactions with applications to gas sensing. https://doi.org/10.1016/j.optcom.2008.07.073

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