Broad-spectrum noise-like pulse and Q-switched noise-like pulse in a Tm-doped fiber laser

Abstract

We experimentally and numerically study the broad-spectrum noise-like pulse (NLP) in a Tm-doped fiber laser (TDFL). The 3-dB spectral width of the NLP is 126 nm, which is, to the best of our knowledge, the broadest spectrum that has been directly obtained from negative dispersion TDFLs. The NLP can transform into another dynamic pulse operation, a Q-switched noise-like pulse (QSNLP). Since the QSNLP showed a noise-like structure within a Q-switched envelope, compared to conventional Q-switched mode-locked pulse, it is break-free during amplification. It offers excellent potential for obtaining high-energy pulses. The numerical studies demonstrate the existence of the NLPs and the rationality of the existence of QSNLP based on the experiment condition. Our work also enriches the operation of bunching structure pulses in fiber lasers.