Fig. 1. Diagram of the GIMF-based saturable absorber.

Fig. 2. Saturable absorption properties of stretched-GIMF SAs measured by the twin-detector measurement technique.

Fig. 3. (a) Nonlinear absorption curve and (b) linear transmission of the GIMF-SA device. Inset: Original spectrum of the broadband source.

Fig. 4. Diagram of the large energy soliton oscillator. Red arrow represents the laser direction. WDM, wavelength division multiplexer; EDF, Er-doped fiber; PI-ISO, polarization independent isolator; PC, polarization controller; OC, optical coupler.

Fig. 5. Output characteristics of the mode-locking operation in the anomalous dispersion region. (a) Output power and pulse energy versus the pump power. (b) Optical spectrum at the maximum pump power. (c) Corresponding autocorrelation trace of the mode-locked pulse; inset is the autocorrelation trace with a large range of 150 ps. (d) Corresponding fundamental frequency of the RF spectrum; inset is the wideband RF spectrum within the 400 MHz span. (e) Digital oscilloscope image. (f) Spectral width and pulse width versus the pump power.

Fig. 6. Measured laser output power over 15 h.

Fig. 7. Output characteristics of the mode-locking operation in the anomalous dispersion region. (a) Output power and pulse energy versus the pump power. (b) Optical spectrum at the maximum pump power. (c) Corresponding autocorrelation trace of mode-locked pulse. (d) Corresponding fundamental frequency of the RF spectrum. (e) Digital oscilloscope image. (f) Spectral width and pulse width versus the pump power.