We report high power all fiber mid-infrared (mid-IR) supercontinuum (SC) generation in a single-mode ZBLAN (ZrF_4- BaF_2-LaF_3-AlF_3-NaF) fiber with up to 21.8 W average output power from 1.9 to beyond 3.8 μm pumped by amplified picosecond pulses from a master oscillator power amplifier (MOPA) based on small-core single-mode thulium-doped fiber (TDF) with injected seed pulse width of 24 ps and repetition of 93.6 MHz at 1963 nm. The optical-optical conversion efficiency from the 793 nm pump laser of the last stage thulium-doped fiber amplifier (TDFA) to mid-IR SC output is 17%. It is, to the best of our knowledge, the highest average power mid-IR SC generation in a ZBLAN fiber to date. In addition, a noise-like fiber oscillator based on a nonlinear loop mirror (NOLM) with wavepacket width of ~1.4 ns and repetition rate of 3.36 MHz at 1966 nm is also used as a seed of the MOPA for mid-IR SC generation in the ZBLAN fiber. At last, a mid-IR SC from 1.9 to beyond 3.6 μm with average output power of 14.3W, which is limited by injected noise-like pulses power, is generated. The optical-optical conversion efficiency from the 793 nm pump laser of the last stage TDFA to mid-IR SC output is 14.9%. This proves the amplified noise-like pulses are also appropriate for high power mid-IR SC generation in the ZBLAN fiber.

Date Published: 4 March 2015
PDF: 6 pages
Proc. SPIE 9344, Fiber Lasers XII: Technology, Systems, and Applications, 93440Z (4 March 2015); doi: 10.1117/12.2079444

Published in SPIE Proceedings Vol. 9344:
Fiber Lasers XII: Technology, Systems, and Applications
L. Brandon Shaw, Editor(s)