Spectrally tailored mid-infrared super-continuum generation in a buried waveguide spanning 1750 nm to 5000 nm for atmospheric transmission

Abstract

We show how nonlinear spectral broadening in a buried chalcogenide mid-infrared waveguide can be used to reshape the spectrum of a femtosecond pulse train at 4260 nm in order to reduce the effects of atmospheric absorption due to carbon dioxide. The nonlinear spectral broadening results in the source with −20 dB spectral width spanning over 3500 nm, from 1700 nm to 5200 nm. This represents a potential route to tailored sources for long-range mid-infrared applications.

Refractive index and dispersion control of ultrafast laser inscribed waveguides in gallium lanthanum sulphide for near and mid-infrared applications

“…This growing interest creates the need for new host materials suitable for integrated optical devices that operate in mid-IR and ChGs are proving to be an excellent solution due to their excellent mid-IR transparency. ChGs provide high optical nonlinearities which coupled with their mid-IR transparency define them as excellent hosts for supercontinuum generation mid-IR sources for sensing applications [9][10][11][12]. Furthermore ChGs can be readily doped with rare earth elements.…”

A novel chalcohalide fiber with high nonlinearity and low material zero‐dispersion via extrusion

“…A 16‐cm long fiber was pumped for SC generation. As centering the pump wavelength on the absorption peak can enable nonlinear spectral broadening, we chose 2.9 μm and 6.3 μm as the pumping wavelengths. Due to high peak laser power and strong nonlinearity, the spectrum will be reshaped quickly and thus not be influenced by the absorption peak .…”

Ge22As20Se58 glass ultrafast laser inscribed waveguides for mid-IR integrated optics

“…For this work, a waveguide array was fabricated containing 7 waveguides with core widths ranging from 2 to 8 μm and core heights of 15 μm (which are referred to as WG1-7 in order of ascending core width and shown in Fig. 1) Waveguide core dimensions were chosen based on mid-IR ULI waveguides produced in other chalcogenide glasses [6]. Once inscribed, the waveguide end facets were ground back and repolished to remove any defects caused by clipping of the writing beam at the sample edges, creating waveguides of 8 mm in length.…”

“…Intrinsically, chalcogenide glasses have a large nonlinear response due to the polarizability of the heavier chalcogen elements they contain and the covalent bonding they exhibit. Chalcogenide glasses can have n 2 values up to ~1000 larger than that of fused silica and are therefore suitable for applications in compact sources of mid-IR supercontinuum [5,6].…”