Characterization of Four-Wave Mixing in Specialty Silica Fibers at 2 μm Using Continuous-Wave Pumps

We report the characterization of continuous-wave four-wave mixing (FWM) in SM1950 and SMF-28 silica fibers in the 2 μm wavelength band. Maximum conversion efficiencies of -21 dB and -25 dB are achived for SM1950 and SMF-28 fibers, respectively. In order to explore multichannel wavelength conversion at 2 μm, we characterize the wavelength conversion of a three-tone signal, which is generated by intensity modulation of a laser using a 10 GHz radio frequency (RF) signal. For all the three channels, we achieve a conversion efficiency of -25 dB using a 21.8 dBm pump. Recent demonstrations of efficient splicing of hollow-core fibers, which have been proposed for optical communications at 2 μm, with silica-based fibers paves the way for all-optical processing of multi-channel signals such as orthogonal frequency-division multiplexing (OFDM).