Hematite (α-Fe2O3), as one of the most prevalent transition metal oxides (TMOs) on the Earth, has been the hot spot of intense research for recent decades. Understanding the optical signatures in hematite is essential for the design of α-Fe2O3-based devices in the photoelectrochemical and photonic fields. In the present work, we successfully synthesized hematite nanoflakes by the facile oil bath method. The small signal transmission of the prepared few-layered hematite nanoflakes was 76% and the modulation depth was determined as 11.2%. Subsequently, the α-Fe2O3 nanoflakes were successfully implemented as the saturable absorber in a passively Q-switched Tm:YLF laser around 2 µm. The achieved shortest pulse duration was 293 ns. The long-term pulse-pulse fluctuation was < 3% in root-mean square error (RMSE), indicating the Q-switching pulses are highly stable. The present work will assist in understanding the nonlinear optical features and their interpretation in stable Q-switching pulses generation.

中文翻译：

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用于稳定中红外脉冲生成的少层 α-Fe2O3 纳米片可饱和吸收体

赤铁矿 (α-Fe2O3) 作为地球上最普遍的过渡金属氧化物 (TMO) 之一，一直是近几十年来研究的热点。了解赤铁矿中的光学特征对于光电化学和光子领域中基于 α-Fe2O3 的器件的设计至关重要。在目前的工作中，我们通过简便的油浴法成功合成了赤铁矿纳米薄片。制备的少层赤铁矿纳米薄片的小信号传输率为76%，调制深度为11.2%。随后，α-Fe2O3 纳米薄片成功地用作约 2 µm 的被动调 Q Tm:YLF 激光器中的可饱和吸收体。实现的最短脉冲持续时间为 293 ns。长期脉搏波动的均方根误差 (RMSE) < 3%，表明 Q 开关脉冲高度稳定。目前的工作将有助于理解非线性光学特征及其在稳定 Q 开关脉冲生成中的解释。