Zhang Wenfei, Wang Guomei, Xing Fei, Man Zhongsheng, Zhang Fang, Han Kezhen, Zhang Huanian, Fu Shenggui
Opt Express. 2020 May 11;28(10):14729-14739. doi: 10.1364/OE.392944.
Various two-dimensional (2D) materials show unique optical properties and excellent performance in acting as saturable absorber (SA) for demonstrating all-fiber ultra-fast lasers. Tellurene, as a new-fashioned few-layer 2D monoelemental material, was designed as an excellent saturable absorber to achieve Q-switched and mode-locked operations within erbium-doped fiber (EDF) lasers in our experiment. High-quality tellurene-based SA with a modulation depth of 0.97% was obtained by blending few-layer tellurene nanosheet solution prepared by liquid phase exfoliation method and the polyvinyl alcohol (PVA) solution. Inserting the SA into the EDF laser cavity by sandwiching the tellurene-PVA film between two fiber ferrules, either the passively Q-switched or the passively mode-locked operations can be obtained. The repetition rate varies from 15.92 to 47.61 kHz, and the pulse duration decreases from 8.915 to 5.196 µs in the passively Q-switched operation. To the best of our knowledge, this is the first demonstration focusing on the modulation application of tellurene in designing Q-switched pulsed laser operations. Additionally, mode-locked operations were also achieved by adjusting the polarization state. The obtained results fully indicate that tellurene can be developed as an efficient SA for pulsed fiber lasers.
各种二维（2D）材料在用作可饱和吸收体（SA）以演示全光纤超快激光器方面表现出独特的光学特性和优异性能。碲烯作为一种新型的少层二维单元素材料，在我们的实验中被设计为一种优异的可饱和吸收体，以在掺铒光纤（EDF）激光器中实现调Q和锁模运转。通过将采用液相剥离法制备的少层碲烯纳米片溶液与聚乙烯醇（PVA）溶液混合，获得了调制深度为0.97%的高质量碲烯基可饱和吸收体。通过将碲烯 - PVA薄膜夹在两个光纤插芯之间，将该可饱和吸收体插入EDF激光腔中，可实现被动调Q或被动锁模运转。在被动调Q运转中，重复频率在15.92至47.61 kHz之间变化，脉冲持续时间从8.915 μs减小到5.196 μs。据我们所知，这是首次聚焦于碲烯在设计调Q脉冲激光运转中的调制应用的演示。此外，通过调整偏振态也实现了锁模运转。所获得的结果充分表明，碲烯可被开发为一种用于脉冲光纤激光器的高效可饱和吸收体。
