Optical quality metal organic framework (MOF) thin films were integrated, for the first time, to the best of our knowledge, with structured optical fiber substrates to develop MOF-fiber sensors. The MOF-fiber structure, UiO-66 (Zr-based MOF is well known for its water stability), is a thin film that acts as an effective analyte collector. This provided a Fabry-Perot sensor in which concentrations of up to 15 mM Rhodamine-B were detected via wavelength shifts in the interference spectrum.

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We demonstrate the application of a Fluorescence Intensity Confocal Optical Microscopy technique to the determination of the relative erbium ion distribution in optical fibers. As well as being able to acquire two dimensional profiles of the relative erbium ion distribution, this method can also provide valuable information on a sub-micron level regarding physical and optogeometric parameters of the examined samples.

The relative distribution of five elements present in the core area of several optical fiber samples has been obtained by utilizing nanoscale-secondary ion mass spectrometry. A strong correlation between the rare-earth (RE) ion and aluminum was observed, consistent with aluminum's improving the solubility of the RE ion. The central dip in distribution was less severe than that observed for germanium, characteristic of the collapse process during fabrication of the fiber preform.

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The effect of very high-temperature exposure on the measurement properties of a fluorescence intensity ratio based optical fiber temperature sensor, using Nd3+-doped fiber as the sensing material, has been investigated. The results obtained indicate that exposing the sensor material to 750 °C for 100 h improves the accuracy of the fluorescence intensity ratio versus temperature characteristics from approximately 2.5 to approximately 1.3 °C. Measurements of the refractive index profiles of Nd3+-doped fiber samples prior to and after exposure to 750 °C indicate that such exposure results in small but measurable changes in the refractive index profile.