We report on the experimental demonstration of a white-light supercontinuum generation in normally dispersive singlemode air-silica microstructured fiber. We demonstrate that the simultaneous excitation of the microstuctured fiber in its normal and anomalous dispersion regimes using the fundamental and second harmonic signals of a passively Q-switched microchip laser leads to a homogeneous supercontinuum in the visible range. This pumping scheme allows the suppression of the cascaded Raman effect predominance in favor of an efficient spectrum broadening induced by parametric phenomena. A flat supercontinuum extended from 400 to 700 nm is achieved.

We present an experimental study on supercontinuum generation with high spectral power density by using a commercial nonlinear fiber amplifier. This new approach consists in the simultaneous combination of the amplification of a pulsed seed signal at 1.06 microm and its peak-power-induced spectral broadening as the optical pulse propagates along the amplifying fiber. A 750-nm broadening from 1 microm to 1.75 microm with tunable spectral power density according to the amplifier gain level is obtained. Spectral power density in excess of 3 mW/nm is demonstrated.

We demonstrate that 2-W average-fpower 310-nm-wide continua can be generated in holey fibers by use of a novel 6-W pump source at 770 nm. The pump source is demonstrated by use of the 64% efficient quasi-phase-matched second-harmonic generation of a seeded 10-W erbium fiber amplifier in periodically poled KTP. Nonlinear contributions to generation of high-power continua in holey fibers are identified and analyzed.

A 3.5 W fiber-based laser source at 772 nm is demonstrated by using quasiphase-matched second-harmonic generation of a 40 dBm seeded ytterbium–erbium fiber amplifier in PPKTP. A 40% conversion efficiency is achieved across the entire output power range of the EDFA. No optical damage has been observed in the PPKTP over long-term high-power exposure.

We generated 56 mW of average power at 384 nm in periodically poled lithium tantalate by use of a visible fiber source based on a variable-pulse format seeded Yb-Er amplifier and frequency upconversion in periodically poled KTP. The feasibility of high-average-power, wide ultraviolet wavelength-range fiber-based sources is evaluated.