Enhanced Q-switched pulse generation at 1.5 μm in erbium-doped fiber laser using Thin-Film Dititanium Tin Carbide as a saturable absorber

In this study, we demonstrate the utilization of a saturable absorber (SA) based on the Thin-Film Dititanium Tin Carbide (Ti2SnC), a novel MAX phase material, in a Q-switched erbium-doped fiber laser (EDFL) operating at 1.5 mu m. The Ti2SnC was effectively integrated with an EDFL cavity to modulate cavity loss and facilitate Q-switching. The resultant SA was produced through a synergistic combination of Ti2SnC and polyvinyl alcohol (PVA), forming a thin film. The Q-switched operation exhibited high stability, achieving an impressive signal-to-noise ratio (SNR) of 65.41 dB. The laser operated within a pump power range of 67.75 mW to 115.99 mW, correlating to a laser diode current of 130-220 mA. This resulted in output power ranging from 2.33 to 6.65 mW, exhibiting a slope efficiency of 1.57%. The Q-switched laser generated pulses at a wavelength of 1531.25 nm, with the repetition rate varying from 64.18 kHz to 105.9 kHz. This corresponded to a pulse width between 5.68 and 3.00 mu s. The maximum pulse energy obtained in our study was 62.80 nJ. Additionally, the 3 dB spectral bandwidth was measured to be 1.3 nm. These experimental results highlight the potential of Ti2SnC, as a costeffective, efficient, and practical option for saturable absorbers in Q-switched fiber lasers, thereby paving the way for further developments in photonic applications.