An ultra-flat and ultra-broadband supercontinuum (SC) is demonstrated in a 4-m photonic crystal fiber (PCF) pumped by an Yb-doped all-fiber noise-like pulses (NLP) laser. The Yb-doped fiber laser is seeded by a SESAM mode-locked fiber laser, and amplified by cascaded fiber amplifiers, with its center wavelength, repetition frequency and the average noise-like bunch duration of 1064.52 nm, 50.18 MHz, 9.14 ps, respectively. Pumped by this NLP laser, the SC source has a 3 dB bandwidth and a 7 dB bandwidth (ignore the pump residue) of 1440 nm and 1790 nm at the maximum average output power of 6.94 W. To the best of our knowledge, this flatness is significantly prominent for the performance of PCF-based SC sources.
A high power diode-pumped continuous-wave Tm:YAP laser with a piece of silicon chip as the output coupler (Si-OC) is demonstrated. A maximum output power of 13 W with a beam quality of M<sup>2</sup> ≤ 1.45 at 1931 nm was obtained, corresponding to an optical-to-optical efficiency of 31%, and a slope efficiency of 33%. To our best knowledge, this is the first report of utilizing silicon as a output coupler on solid Tm:YAP laser system. The mechanism of silicon output coupler on Tm:YAP laser is also discussed in this letter. Because of the intriguing characteristics of silicon, such as high damage threshold, low cost and long-pass filter property, double-sided polishing single crystal silicon chip can perform as a good output coupler in high power laser system near 2 μm region.