Experimental research of high conversion efficiency all-fiber supercontinuum source

An all-fiber supercontinuum generation system has been demonstrated. In the system, a short matching fiber was used to reduce the loss in the connection of the gain fibers and the photonic crystal fiber, and real-time measurement was carried out in the splicing stage to minimize the loss. Such techniques ensure a whole system conversion efficiency of 76% and a good beam quality. The broadening process was analyzed experimentally and interpreted as follows. More broadened spectrum lies in the long wavelength region rather than in the short wavelength one, which indicates that Raman effect and self-phase-modulation dominate the initial broadening process. Meanwhile, Raman-Stocks peaks were obvious. As the broadening developing, the phase matched parametric four-wave mixing begins to occur, a