Highly nonlinear chalcogenide hybrid microstructured optical fibers with buffer layer and their potential performance of supercontinuum generation

We report here the design of a new chalcogenide hybrid microstructured optical fiber (HMOF) with a buffer layer around the core and its potential performance of tailoring chromatic dispersion and supercontinuum (SC) generation. The new chalcogenide HMOF has an AsSe2 core. The refractive index difference Delta n between the AsSe2 core and cladding material is supposed to be 0.3. The fiber microstructure and the Delta n between the core and buffer materials are designed in order to obtain broad anomalous dispersion regimes with near-zero and flattened chromatic dispersion profiles for broadband SC generation. Moreover, the suppression of chromatic dispersion fluctuation caused by fiber transverse geometry variation is investigated. By using the proposed chalcogenide buffer-embed HMOFs, the calculation shows that near-zero and flattened anomalous chromatic dispersion regimes from 4.5 mu m can be obtained. When the variation of fiber structure occurs for +/- 1, +/- 5 and +/- 10 %, the chromatic dispersion fluctuation can be greatly suppressed. In addition, the calculation shows that a broad SC spectrum from 2.5 to more than 16.0 mu m can be obtained when a 0.9-cm-long section of the new chalcogenide buffer-embed HMOF is pumped at 5.0 mu m by a femtosecond laser with 1-kW peak power.