Fig. 1. (a) SEM image for microfiber coated with MoTe2 film. (b) SEM image of the cross section of microfiber. The inset is a magnified SEM image. Optical microscope images of the waist region of sample (c) without and (d) with the guiding red light. (e) Field intensity of the guided mode in the microfiber.

Fig. 2. (a) XPS spectrum of MoTe2 film. (b) XPS core level spectrum of Mo 3d. (c) XPS core level spectrum of Te 3d.

Fig. 3. (a) Linear transmission of MoTe2 film. (b) Saturable absorption properties of the MoTe2 SA. (c) Normalized open-aperture Z-scan traces with the excitation powers of 0.4, 0.6, and 0.86 mW, respectively. (d) Pump–probe measurement of the carrier lifetime of MoTe2.

Fig. 4. (a) XRD patterns of MoTe2 film. The inset shows the film quality with the scale bar of 400 nm. The SEM images with test energy densities of (b) 5.7  mJ/cm2 and (c) 10.8  mJ/cm2, respectively.

Fig. 5. Schematic of the passively mode-locked erbium- or thulium-doped fiber laser.

Fig. 6. Mode-locking pulse output characterizations for the EDF laser. (a) Relationship between the pump power and laser output power. (b) Optical spectrum with the bandwidth of 11.76 nm. (c) Radio frequency spectrum at fundamental frequency of 26.601 MHz with 10 Hz resolution. The inset is the RF spectrum of 1 GHz span. (d) Autocorrelation trace for output pulse with a pulse duration of 229 fs with sech2 fit. The inset shows the autocorrelation trace with a large range of 50 ps.

Fig. 7. Mode-locking pulse output characterizations for the TDF laser. (a) Relationship between the pump power and laser output power. (b) Optical spectrum with the bandwidth of 3.2 nm. (c) Radio frequency spectrum at fundamental frequency of 15.37 MHz with 10 Hz resolution. The inset is the RF spectrum of 1 GHz span. (d) Autocorrelation trace for output pulse with a pulse duration of 1.3 ps with sech2 fit. The inset shows the autocorrelation trace with a large range of 50 ps.