Passively Q-switched erbium-doped fiber laser based on Ti3C2Tx saturable absorber

Abstract

In this work, layer-structured MXene-Ti3C2Tx was successfully synthesized through chemical etching the Al in Ti3AlC2 using hydrochloric acid. The Ti3C2Tx was characterized in detail using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Additionally, a Ti3C2Tx-polyvinyl alcohol (PVA) thin film was prepared, which exhibited modulation depths of 3.8% and a saturation intensity of 418.61 MW/cm2. Passive Q-switched erbium-doped fiber laser built employing Ti3C2Tx-PVA thin film with saturated absorption characteristics. When the pump power is between 68 and 112 mW, Q-switched pulse outputs were achieved. By gradually enhancing the pump power, the pulse repetition frequency enhanced from an initial value of 29.47 kHz to a final value of 47.79 kHz, while the pulse width reduced from 6.1 μs to 3.45 μs. Correspondingly, the output power of the system enhanced from 1.063 mW to 1.847 mW. When the pump power is 112 mW, the maximum single-pulse energy can reach 38.64 nJ. The experimental results have demonstrated the promising potential of Ti3C2Tx-PVA as an effective saturable absorber.