High speed pulse generation with adjustable output characteristics in the mid-infrared (MIR) wavelength is a challenge due to the lack of high speed optoelectronic modulator operating at this band. In this paper, we proposed a MIR actively mode-locked laser based on cross-band all-optical injection modulation. The proposed laser is modulated by injecting 1.55- μ m pump pulses into the specially-designed cross-band group-velocity-matched fiber. By numerical simulation, we studied in detail the evolution mechanism of the pulses and the influence of the cavity parameters on the output pulse features. It is shown that the laser is suitable for high repetition rate pulse generation up to 40 GHz at 2.771 μ m, and the pulse shape can be flexibly adjusted. The proposed MIR laser has great potential in MIR free-space optical (FSO) communication.

中文翻译：

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基于交叉带全光注入调制的中红外高重复锁模激光器

由于缺乏在该频段工作的高速光电调制器，因此在中红外（MIR）波长中具有可调节输出特性的高速脉冲产生是一个挑战。在本文中，我们提出了一种基于交叉带全光注入调制的MIR主动锁模激光器。通过将1.55μm的泵浦脉冲注入经过特殊设计的跨频带群速度匹配光纤中，对所提出的激光器进行调制。通过数值模拟，我们详细研究了脉冲的演化机理以及腔参数对输出脉冲特征的影响。结果表明，该激光器适合在2.771μm的频率下产生高达40 GHz的高重复频率脉冲，并且可以灵活调节脉冲形状。提出的MIR激光器在MIR自由空间光学（FSO）通信中具有巨大的潜力。