Low concentration fluorescence sensing in suspended-core fibers

Abstract

We present improvements to fluorescence sensing in microstructured optical fibers that result in significantly improved sensitivity relative to previously published results. Concentrations of CdSe quantum dots down to 10 pm levels have been demonstrated. We show that the primary limitation to the sensitivity of these systems is the intrinsic fluorescence of the glass itself. We investigate alternative architectures for improved sensitivity by separating the excitation and capture in to separate cores within a single fiber.