Group velocity dispersion of tapered fibers immersed in different liquids

Abstract

We investigate the group velocity dispersion of tapered fibers that are immersed in different liquids. Using the Sellmeier equations fitted from measured refractive indices of these liquids, we are able to analyze the dispersion characteristics of the tapered fibers in a tailored liquid environment. Theoretical results show a large span of slowly varying anomalous group velocity dispersion characteristics. This leads to potentially significant improvements and a large bandwidth in supercontinuum generation in a tapered fiber. This holds true as well for a range of new fiber materials.

Optical microfiber passive components

“…(n 2 and A eff are the material nonlinear refractive index and the beam effective area, respectively) and allows for the prompt observation of nonlinear effects like supercontinuum generation [24][25][26][27][28][29][30][31][32][33][34], third-harmonic generation [21,35], slow and fast light [36] and bistability [37,38] [34]. Highly nonlinear glasses usually are transparent far into the infrared region, thus they can be exploited for the generation of supercontinuum in spectral regions where silica is not transparent [29].…”

Analysis of tunable flat dispersion of germanium doped fiber with liquid cladding

“…However, the high dispersion slope near the ZDW of silica fibers gives rise to a very limiting useful bandwidth as the silica fiber has a very high phonon energy with its ZDW occurring at around 1300 nm. More recently, the dispersive liquid is proposed to surround the tapered fiber to engineer fiber's dispersion and a broadband flattened GVD can be achieved over 1200-1400 nm [4,5]. However, the high-peak-power femto-second mode-locked fiber laser at 1550-nm wavelength band (e.g., Er 3þ -doped fiber laser) can not be used to produce SC with a high generation efficiency and a wide bandwidth.…”

“…The amount of Ge-doping, waveguide diameter d, and index of liquid cladding are key parameters for broadband flattened GVD and wide bandwidth SC. The GVD is defined as the second derivative of propagation constant and is obtained by solving the dispersion equation for HE 11 mode of optical fiber [4]. At the beginning, the diameter of the Ge-doped fiber core was set to be 2.5 lm with the Cargille liquid cladding of n D ¼ 1.40.…”

“…However, these basic topologies are limited to single frequency operation, and, recently, several studies are reported regarding dual-or multiband operation of impedance matching networks. So far, most of the dual-band impedance transformers are based on the two-section cascaded transmission line structure [2][3][4][5]. They are basically a special case of the Chebyshev multisection transformers with equal-length transmission line sections [2][3][4].…”

“…So far, most of the dual-band impedance transformers are based on the two-section cascaded transmission line structure [2][3][4][5]. They are basically a special case of the Chebyshev multisection transformers with equal-length transmission line sections [2][3][4]. Later, this method is extended to the unequal two-section topology for the dual-band matching of the complex impedances [5].…”