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We report on an Er-doped fiber pulse laser at large net normal dispersion cavity by employing a dispersion compensating fiber in combination with a single-walled carbon nanotube (SWCNT) saturable absorber. A SWCNT/polymer composite film uniformly spin-coated on the side-polished fiber is prepared for robust and efficient nonlinear interaction with evanescent fields in the waveguide expecting increase of optical and thermal damage threshold compared to previously reported direct coating of SWCNTs on fiber ferrules. The fabricated dissipative soliton fiber laser exhibits high average output power of 55.6 mW, corresponding to pulse energy about 2.35 nJ. Highly chirped 5.8 ps pulses are generated with a spectral bandwidth of 13.9 nm and compressed down to 226 fs using additional length of conventional optical fiber at extra-cavity.

Passive harmonic mode-locking in soliton fiber laser is presented with excellent noise characteristics by employing a single-walled carbon nanotubes saturable absorber designed to interact with evanescent wave of the laser field. The 34(th) harmonic mode-locking pulses at 943.16 MHz repetition rate were stably generated with 18 mW output power,50 dB side-mode suppression and -140 dB/Hz relative intensity noise. Soliton energy control with polarization controller further increased the harmonic order to 61st, 1.692 GHz, but with compromised performance. Scaling to higher-order harmonic mode-locking is discussed for practical application in optical communication system.