Zhao Xiaoli, Sun Jingxuan, Wang Yachen, Wang Xiaogang, Fu Bo
Key Laboratory of Precision Opto-Mechatronics Technology, School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China.
Key Laboratory of Big Data-Based Precision Medicine Ministry of Industry and Information Technology, School of Engineering Medicine, Beihang University, Beijing 100191, China.
Nanomaterials (Basel). 2024 May 29;14(11):951. doi: 10.3390/nano14110951.
Q-switched fiber lasers have become reliable light sources for generating high-energy pulses, which can be passively modulated by saturable absorbers with excellent nonlinear optical properties. The composite combining Ag and MXene exhibits a broadband nonlinear response and high modulation depth, making it a promising candidate for saturable absorbers in pulsed lasers. Herein, we demonstrate a Q-switched Tm:Ho co-doped fiber laser centered at 2 µm, where the Ag/MXene composite serves as a saturable absorber to generate pulses. The typical spectrum, pulse train, and radio frequency spectrum of Q-switched pulses were observed, in which the 60 dB signal-to-noise ratio was higher than that of 2 µm Q-switched fiber lasers based on other materials, demonstrating the stability of the output pulses. Additionally, the long-term stability of the laser was evaluated over 2 h, where the well-maintained central wavelength and output power also indicated the robustness of the Q-switched laser. Furthermore, the influence of the pump power on the parameters of Q-switched pulses was also investigated, which is conducive to control the output characteristics of lasers. Specifically, the pulse width of the Q-switched pulse decreased, while the repetition rate, output power, and single pulse energy all increased with the increase in pump power. These experimental results demonstrate the ability of Ag/MXene as a saturable absorber and show its potential for generating high-performance pulses in ultrafast lasers.
调Q光纤激光器已成为产生高能量脉冲的可靠光源，其可由具有优异非线性光学特性的饱和吸收体进行被动调制。结合了银和MXene的复合材料展现出宽带非线性响应和高调制深度，使其成为脉冲激光器中饱和吸收体的一个有潜力的候选材料。在此，我们展示了一台中心波长为2 µm的调Q掺铥钬共掺光纤激光器，其中银/MXene复合材料用作饱和吸收体来产生脉冲。观察到了调Q脉冲的典型光谱、脉冲序列和射频光谱，其中60 dB的信噪比高于基于其他材料的2 µm调Q光纤激光器，证明了输出脉冲的稳定性。此外，在2小时内评估了激光器的长期稳定性，良好保持的中心波长和输出功率也表明了调Q激光器的稳健性。此外，还研究了泵浦功率对调Q脉冲参数的影响，这有利于控制激光器的输出特性。具体而言，调Q脉冲的脉宽减小，而重复频率、输出功率和单脉冲能量均随泵浦功率的增加而增加。这些实验结果证明了银/MXene作为饱和吸收体的能力，并展示了其在超快激光器中产生高性能脉冲的潜力。
