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Contents. Optical Fibers ; Optical Fiber Sensors; Microstructured Optical Fibers ; Suspended Core Fibers : Tapering; Setup; Spectral Response; Strain and Temperature Characterization; Conclusions. n 1. n 2. n 1. Optical Fiber.
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Contents • Optical Fibers; • Optical Fiber Sensors; • Microstructured Optical Fibers; • Suspended Core Fibers: • Tapering; • Setup; • Spectral Response; • Strain and Temperature Characterization; • Conclusions. Ricardo Melo André
n1 n2 n1 OpticalFiber • Differentrefractive índices in core andcladding; • Propagationby total internalreflection. Ricardo André - ENEF XII
Optical Fiber Sensors • How can we use Optical Fibers as sensors? DL/L DT Ricardo Melo André - IJUP 2010 - February 18 2010
Microstructured OpticalFibers (MOFs) • PhotonicCrystalFibers (PCFs): • Index guiding PCFs • Photonic bandgap PCFs. • OtherMOFs: • Suspended Core Fibers, BraggFibersandothers. Ricardo André - ENEF XII
Tapering of Suspended Core Fiber • VYTRAN GPX-3000 • Tapering of microstructured optical fibers with extreme control; Ricardo Melo André
Suspended Core Fiber Tapers • Tapers down to 20 μm of external diameter: • Nanocore diameter of 330 nm. • No hole collapse; • Cladding guidance below 600-700 nm core. 125 μm fiber 2.1 μm core 810 nm fiber Ricardo Melo André
Fiber Loop Mirror Setup • Erbium-doped broadband source (1550 nm); • Optical Spectrum Analyzer • 3 dB coupler; • Polarization controller; • Suspended-core fiber section with taper. Ricardo Melo André
Spectral Response Analysis • Two interferometers: • High Birefringence; • Intermodal Interference; • Higher visibility; • Cleaner spectrum (only birefringence). Ricardo Melo André
Strain Characterization • Strain sensitivity increase with taper waist diameter decrease. • 2.1 μm core • 0.718 pm/με • 810 nm core • 2.41 pm/με Ricardo Melo André
Temperature Characterization • 2.1 μm core • 2.1 pm/K • 810 nm core • 56.2 pm/K • At lower diameters, higher birefringence dependence on temperature. Ricardo Melo André
Conclusions • Nanowire Characteristics: • High degree of protection / Independence of external medium; • Triangular, highly birefringent shape; • High temperature sensitivity; • Enhanced strain sensitivity; • High spectral stability; • Clean and easy-to-read spectrum; Ricardo Melo André
Acknowledgments • COST TD1001 Information and Communication Technologies; • Institute of Photonic Technology, Jena, Germany; • Dr. Orlando Frazão and Prof. Manuel B. Marques; • Thanks for your attention. Ricardo Melo André