Tm-Ho Codoped Fiber Based All Fiber Amplification Of A Gain-Switched 2 Mu M Fiber Laser

A Tm-Ho codoped fiber amplifier system is built. And, amplification of a gain-switched Tm-Ho codoped fiber laser is investigated. Average output of 300 mW is obtained at repetition rate of tens of kHz with an amplification gain bigger than 11 dB. And, pulse amplification efficiency of resonantly pumped Tm-Ho codoped single clad fiber is comparable with 793 nm pumped Tm-doped double clad fiber. The maximal pulse energy generated is about 13.1 mu J, corresponding to a peak power of 282 W at 20 kHz. During the amplification process, gain-switching, partially modulated gain-switched mode-locking and 100% modulated gain-switched mode-locking are observed sequentially. At gain-switching mode, the laser output enjoys a narrow linewidth of 0.31 nm, while at gain-switched mode-locking mode, the spectral linewidth broadens to 0.6 nm. (C) 2014 Elsevier GmbH. All rights reserved.