We report an integrated whispering gallery mode microresonator-based sensor probe for refractive index sensing. The probe was made by sealing a borosilicate glass microsphere into a thin-wall glass capillary pigtailed with a multimode optical fiber. The intensities of the resonant peaks were found decreasing exponentially (linearly in a log scale) with the increasing refractive index of the medium surrounding the capillary. The sensing capability of the integrated probe was tested using sucrose solutions of different concentrations and the resolution was estimated to be about 2.5 x 10-5 in the index range of 1.3458 to 1.3847. The integrated sensor probe may prove useful in many chemical and biological sensing applications where highly sensitive refractive index monitoring is needed.
H. Wang et al., "Integrated Microsphere Whispering Gallery Mode Probe for Highly Sensitive Refractive Index Measurement," Optical Engineering, vol. 55, no. 6, SPIE, Jun 2016.
The definitive version is available at https://doi.org/10.1117/1.OE.55.6.067105
Mining and Nuclear Engineering
Electrical and Computer Engineering
National Institutes of Health (U.S.)
Keywords and Phrases
Borosilicate glass; Microspheres; Multimode fibers; Optical fibers; Optical resonators; Probes; Refractive index; Refractometers; Thin walled structures; Chemical and biological sensing; Glass capillaries; Integrated sensors; Multimode optical fibers; Refractive index measurement; Refractive index sensing; Refractive index sensor; Thin walls; Whispering gallery modes; Thin wall capillary
International Standard Serial Number (ISSN)
Article - Journal
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