GVD measurement in single-mode optical fibers in the 1.7-2 μm wavelength range

The setup based on Mach-Zehnder interferometer for group-velocity dispersion (GVD) measurements in single-mode optical fibers in the 1.7-2 μm wavelength range was developed. A high numerical aperture Tm-doped fiber pumped at 1.61 μm wavelength by a CW Er-doped fiber laser was used as a light source. The optical power of the amplified spontaneous emission of ~50 nm full width at half maximum band reached 5 mW which, to our knowledge, overcome the optical power of the best commercially available superluminescent semiconductor lasers. The GVD in the set of short-length (~80 cm) single-mode fibers was measured to proof the reliability of the setup. Namely, the highly-germanium-doped core fibers (undoped and co-doped with thulium) and standard telecommunication fibers were studied to show the wide capabilities of our setup.