Management of OH absorption in tellurite optical fibers and related supercontinuum generation

Infrared fibers

“…Over the past decade, the high optical nonlinearity of tellurite glasses [63,167,168] has attracted interest for applications in IR nonlinear optical processing [169][170][171][172]. Critically, from the perspective of fiber drawing, the glasses exhibit high crystallization stability relative to fluoride glasses, so they may be readily shaped into a large variety of preform structures using casting [164,173,174], drilling [175], and extrusion techniques [176]; see Fig. 9.…”

“…Replacing silicon with heavy metals (e.g., lead and tungsten) results in oxide glasses with their transparency window extending further into the IR, albeit not as far as fluoride and chalcogenide glasses. and the use of fluoride or chloride raw materials and combinations thereof, have been investigated to reduce the OH content in tellurite glasses, and recent results are listed in Table 3 [164,[173][174][175][176][177][178][179][180][181][182][183][184]. The OH content in tellurite glasses is caused by water impurities in the raw materials.…”

Enhanced supercontinuum generation in tapered tellurite suspended core fiber

“…3(a)). It also includes Kerr effect (nonlinear Kerr coefficient is deduced from numerical calculation of effective area, and with nonlinear refractive index n 2 ¼3.8 Â 10 -19 m 2 /W [36]), self-steepening term with dispersion of the nonlinearity and the Raman response function for our TZN glass adapted from Ref. [37].…”

Mid-infrared supercontinuum generation in soft-glass suspended core photonic crystal fiber

“…Since characteristic nonlinear length scale calculated for this fiber was much shorter than its dispersive length scale (0.3 mm against 7 cm), we assumed the broadening should occur fast, ie. in the first few mm, up to 1 cm (Savelii et al 2013;Dudley and Taylor 2010). Hence the sample length was a matter of cutting convenience.…”

“…Further improvements to glass synthesis are necessary to overcome this issue. OH − concentrations as low as 1 ppm (0.1 dB/m loss) were recently reported in oxide tellurite glass fibers, where glass synthesis incorporated in-house purification of commercial raw materials, as well as replacement of OH − ions with fluorine ions (Savelii et al 2013). Fiber sample used in our experiment was not end-capped.…”