Towards integration of a liquid-filled fiber capillary for supercontinuum generation in the 12–24 μm range

Abstract

We demonstrate supercontinuum generation in unspliced as well as in integrated CS(2)-filled capillary fibers at different pump wavelengths of 1030 nm, 1510 nm, and 1685 nm. A novel method for splicing a liquid-filled capillary fiber to a standard single-mode optical fiber is presented. This method is based on mechanical splicing using a direct-laser written polymer ferrule using a femtosecond two-photon polymerization process. We maintain mostly single-mode operation despite the multi-mode capability of the liquid-filled capillaries. The generated supercontinua exhibit a spectral width of over 1200 nm and 1000 nm for core diameters of 5 μm and 10 μm, respectively. This is an increase of more than 50 percent compared to previously reported values in the literature due to improved dispersion properties of the capillaries.

Hybrid soliton dynamics in liquid-core fibres

“…Hence, spectral broadening in LiCOFs has mainly been demonstrated in the normal dispersion regime so far. Large Raman gains were shown in CS 2 -core step-index fibres 30, 31 , and supercontinuum generation based on SPM was achieved, featuring spectral bandwidths of up to 1.2 μm (127 THz) 32, 33 . However, soliton-based light generation has not been directly targeted in CS 2 -LiCOFs, yet.…”

“…The coupling is stable over several days under atmospheric pressure and even while flushing the optofluidic mounts with flow rates up to 10 ml min −1 . The set-up was kept under pressure, between 4 and 6 bar (at 20 °C), to avoid bubble formation as reported earlier 32, 33 , which in fact turned out not to be crucial for the pump wavelength considered here.…”

Hybrid Optical Fibers – An Innovative Platform for In‐Fiber Photonic Devices

“…To provide total internal refl ection at the liquid-solid interface and a suffi ciently high optical nonlinearity, low-molecular weight liquids with high refractive index such as carbon-disulfi de [ 154 ] or carbon tetrachloride [ 155 ] are used in selectively fi lled PCFs or capillaries. One particular interesting feature of liquid core fi bers is the emergence of a retarded optical nonlinearity, which is a result of a torque applied to the individual molecules of the liquid when being exposed to strong femtosecond pulses.…”

Highly coherent supercontinuum generation in a polarization-maintaining CS2-core photonic crystal fiber

“…Churin et al obtained mid-infrared SC of over 600 nm in an integrated CS2-core PCF [32]. Kedenburg et al generated the SC of over 1000 nm through optimizing the dispersion profile of a CS2-core PCF [33]. However, there is still no report on the nonlinear optical dynamics and SC generation in the CS2-core PCF with high birefringence.…”