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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几层α -Fe ₂ O ₃纳米片状可饱和吸收剂，可稳定产生MIR脉冲

赤铁矿（α-的Fe ₂ ö ₃），作为地球上最普遍的过渡金属氧化物（TMOS）之一，已深入研究的热点近几十年来。在赤铁矿理解的光学特征是α-Fe的设计必需_2台ö ₃系设备在光电化学和光子字段。在目前的工作中，我们通过简便的油浴方法成功地合成了赤铁矿纳米片。所制备的几层赤铁矿纳米薄片的小信号传输为76％，调制深度确定为11.2％。随后，的α-Fe ₂ ö ₃在约2 µm的被动调Q的Tm：YLF激光器中，纳米片成功地用作可饱和吸收体。达到的最短脉冲持续时间为293 ns。长期脉冲脉冲波动的均方根误差（RMSE）<3％，这表明Q开关脉冲非常稳定。本工作将有助于理解非线性光学特征及其在稳定的Q开关脉冲产生中的解释。