Performance of Nb2C MXene coated on tapered fiber as saturable absorber for the generation of Mode-Locked Erbium-Doped fiber laser

In this study, we demonstrated the potential of Nb2C MXene, which is a member of the MXene family, as a saturable absorber (SA) material in generating ultrafast laser at C-band wavelength region. The fabricated tapered fiber with a diameter of 3.56 ?m was coated with Nb2C MXene to realize the interaction of the evanescent field with the material used, hence induced the generation of mode-locked pulses. The investigation on the nonlinear optical properties of the fabricated SA shows that it had a modulation depth and saturation intensity of 12.94% and 1.1 kW/cm2, respectively. The soliton pulse with pulse duration of 0.77 ps at the central wavelength of 1559 nm was successfully generated at the pump power of 90.88 mW upon the insertion of the Nb2C MXene SA into the EDF laser cavity. The fundamental mode has a repetition rate of 14.12 MHz within pump power ranging from 90 to 473 mW. The maximum output power, pulse energy and peak power obtained from the mode-locked laser was measured to be 3.04 mW, 212.7 pJ and 0.18 kW, respectively. A signal to noise ratio (SNR) of approximately 66.5 dB was obtained, hence suggests that the generated mode-locked fiber laser possess an excellent stability. The present findings would open a window of opportunity to a new device for Nb2C MXene intended for high-performance mode-locked lasers.