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We present a detailed comparison between modeling and experiments on supercontinuum (SC) generation in a commercial ZBLAN step-index fiber. Special emphasis is put on identifying accurate material parameters by incorporating measurements of the ZBLAN Raman gain, fiber dispersion, and loss. This identification of accurate parameters is of great importance to substantiate numerical simulations of SC generation in soft-glass fibers. Good agreement between measurement and simulation is obtained when pumping both in the normal and anomalous dispersion regimes.

Abstract:Combining the molecular specificity of the infrared spectral region with high resolution microscopy has been pursued by researchers for decades. Here we demonstrate infrared supercontinuum radiated from an optical fiber as a promising new light source for infrared microspectroscopy. The supercontinuum light source has a high brightness and spans the infrared region from 1400 nm to 4000 nm. This combination allows contact free high resolution hyper spectral infrared microscopy. The microscope is demonstrated by imaging an oil/water sample with 20 μm resolution. form spectroscopic imaging using an infrared focal-plane array detector," Anal. Chem. 67, 3377-3381 (1995). 18. L. M. Miller and R. J. Smith, "Synchrotrons versus globars, point-detectors versus focal plane arrays: Selecting the best source and detector for specific infrared microspectroscopy and imaging applications," Vib. Spectrosc. 38, 237-240 (2005).

Proton, deuteron, and carbon NMR methods were applied to study various isotopic species of supercooled and glassy propylene carbonate. The molecular diffusion was investigated via static field gradient diffusometry and yielded evidence for a particularly pronounced enhancement of the translational over the reorientational dynamics. The latter was monitored using measurements of spin−lattice relaxation times and of two−time stimulated echoes. The sinâ€"sin correlation functions exhibited a pronounced dependence on the evolution times. From these results it is concluded that the geometry of molecular reorientation can be described as a superposition of moderately small jump angles (about 30˚) and a quasi−diffusive component which is responsible for about one−third of the total angular displacement. Finally, four−time stimulated echoes confirmed that the nonexponential relaxation in propylene carbonate is dynamically heterogeneous in nature. ©2000 American Institute of Physic

A detailed comparative study of the optical properties of two rare-earth (RE) sesquisulfide compounds γ−Ce2S3 and γ−Gd2S3, shows that if the two compounds have about the same main absorption edge corresponding to band-to-band S 3p-RE 5d transitions, Ce2S3 exhibits an additional absorption band at lower energies. This band, which is ascribed to the presence of Ce 4f states at the top of the valence band, explains the difference in color between the two compounds.