Q-switched Yb-doped fiber laser operating at 1073 nm using a carbon nanotubes saturable absorber

A stable passive Q-switched Ytterbium-doped fiber laser (YDFL) operating at 1073-nm region is demonstrated using single-walled carbon-nanotubes (SWCNTs) as a saturable absorber (SA). The SA is prepared using polyvinyl alcohol (PVA) as a host polymer and integrated in the YDFL ring cavity by sandwiching the SWCNT/PVA thin film between two fiber connectors. A stable pulse train is achieved with 17.1-kHz repetition rate, 6.45-s pulse width, and 3.1-nJ pulse energy at the threshold 980-nm pump power of 95.4 mW. As the pump power increases to 117.5 mW, the pulse train repetition rate also rises to 23.6 kHz. The shortest pulse width of 3.11 s and pulse energy of 4.4 nJ are achieved at the maximum pump power of 117.5 mW (c) 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1770-1773, 2014