All-fiber polarization maintaining erbium-doped fiber laser based on nonlinear amplifying loop mirror

In this paper, all-fiber based all polarization maintaining erbium-doped fiber lasers based on nonlinear amplifying loop mirror (NALM), including both figure-of-8 and figure-of-9 configurations are demonstrated. The figure-of-8 oscillator generates 1.6 ps chirped pulses at 1550 nm with a pulse energy of 0.8 nJ and a repetition rate of 12 MHz. The figure-of-9 oscillator generates 420 fs pulses at 1550 nm with a pulse energy of 0.2nJ and a repetition rate of 52.5 MHz. Both configurations have the advantages of self-starting and long term operation.