We demonstrate two flat plateaus and the low-noise spectrum of supercontinuum generation (SCG) in a highly nonlinear fiber (HNLF), injected by an amplified picosecond pulse seed of a carbon nanotube-based passively mode locked erbium-doped fiber laser. A broad spectrum of width approximately 1090 nm spanning the range 1130-2220 nm is obtained and the pulse width is compressed to the shorter duration of 70 fs. Variations of the injected peak power up to 33.78 kW into the HNLF are compared and the broad spectrum SCG profiles slightly expand for each of the injected peak powers. This straightforward configuration of SCG offers low output power and ultra-narrow femtosecond pulse width. The results facilitate the development of all fiber time-domain spectroscopy systems based on the photoconductive antenna technique.

A carbon nanotube thin film as saturable absorber in a cavity design of mode-locked fiber laser is reported in this work. Measured by power dependent absorption setup, 22% modulation depth of the saturable absorber is estimated which is ideal for stabilizing the mode-locked operation. Based on the scanning image from atomic force microscope (AFM), Single wall carbon nanotube components are identified existed in the thin film. The laser cavity employed a ~40 cm long erbium doped fiber as a gain medium which corresponds to the laser wavelength of 1550 nm (telecommunication wavelength region). Total length cavity of the fiber laser is about 3.1 m where shorter cavity design is required for higher repetition rate. This proposed system result in a firm soliton spectrum at centre wavelength of ~1561 nm with ~0.7 mW average output power and pulse duration of 410 fs. The pulses are generated at fundamental repetition rate of 68 MHz without any distortion and excellent spectral quality.

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A Q-switched Erbium-doped fiber laser (EDFL) was demonstrated utilizing Bismuth Salenide (Bi 2 Se 3) as a saturable absorber. The saturable absorber (SA) is fabricated by mixing directly the Bismuth Salenide (Bi 2 Se 3) into polyvinyl alcohol (PVA) aqueous solution to form a thin film. The SA is integrated into EDFL cavity to achieve a stable Q-switched at center wavelength of 1559.8 nm. The peak power is a steady increasing pattern from 2.52 mW to 3.21 mW as the pump power is increased from 86.1 mW to 116.6 mW. The highest pulse energy obtained was 36.9 nJ at the pump power of 116.6 mW.

The mechanism of evanescent field interaction is established between lutetium oxide (Lu2O3) and light on the surface of D-shaped optical fiber. The D-shaped optical fiber was prepared using rotating wheel technique with the improved two times polishing method. The side-polished fiber sample owns a remaining fiber diameter of 70 μm and polishing length of 1400 μm. Lutetium oxide was deposited onto the D-shaped optical fiber as a pulse initiator inside an erbium-doped fiber laser cavity. A Q-switched with operating wavelength of 1565 nm was generated. Stable pulses were recorded as the pump power raised from 146 to 162 mW with pulse width as short as 450 ns and repetition rate of 0.967 MHz. As the pump power varied, output power of 120 to 160 μW which corresponds to pulse energy of 124 to 166 pJ were obtained.