Experimental realization of 40 Gbit/s single-to-single and single-to-dual channel wavelength conversions in LiNbO3 waveguides with two-pump configuration

An all-optical 40 Gbit/s tunable single-tosingle channel wavelength conversion is experimentally realized based on cascaded sum- and difference-frequency generation (cSFG/DFG) in periodically poled LiNbO3 (PPLN) waveguides. By employing two tunable filters to effectively suppress the amplified spontaneous emission (ASE) noise, both wavelength down- and upconversions are simultaneously observed. We also propose and verify a novel cSFG/DFG-based single-todual channel wavelength conversion by setting two pumps (pumpl, pump2) close to each other or pump2 and the signal close to each other. For the latter, two kinds of cSFG/DFG schemes are both demonstrated The dependence of the conversion efficiencies of two channel idler waves on pumpl wavelength is discussed.The wavelength relationships between two channel idler waves and the three incident waves are investigated in detail theoretically as well as experimentally.