Shu Yiqing, Guo Jia, Fan Taojian, Xu Yijun, Guo Penglai, Wang Zhenhong, Wu Leiming, Ge Yanqi, Lin Zhitao, Ma Dingtao, Wei Songrui, Li Jianqing, Zhang Han, Chen Weicheng
School of Physics and Optoelectronic Engineering, Foshan University, Foshan 528000, China.
Institute of Microscale Optoelectronics, Collaborative Innovation Centre for Optoelectronic Science & Technology, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, Guangdong Laboratory of Artificial Intelligence and Digital Economy (SZ), Shenzhen University, Shenzhen 518060, PR China.
ACS Appl Mater Interfaces. 2020 Oct 14;12(41):46509-46518. doi: 10.1021/acsami.0c12408. Epub 2020 Sep 30.
Black arsenic phosphorus (b-AsP), as one kind of novel two-dimensional (2D) materials, bridges the band gap between black phosphorus and graphene. Thanks to its great advantages, including high carrier mobility, excellent in-plane anisotropy, and broad tunability band gap, b-AsP has aroused great interest in fields of photonics and photoelectronics. In this paper, ultrathin 2D b-AsP nanomaterials were fabricated by the liquid-phase exfoliation method, and their strong broadband linear and nonlinear absorptions were characterized by ultraviolet-visible-infrared and -scan technology. The experimental determination of the nonlinear absorption coefficient and low saturation intensity of b-AsP were -0.23 cm/GW and 3.336 GW/cm, respectively. Based on density functional theory, the partial charge density and band structure at the conduction band minimum and valence band maximum were calculated, which further proves the excellent optical properties of 2D b-AsP. By first using 2D b-AsP as a novel saturable absorber in both erbium-doped and thulium-doped fiber lasers, mode-locked soliton pulses can stably operate at 1.5 and 2 μm. The laser pulses generated by 2D b-AsP possess higher stability to resist self-splitting than those generated by other 2D material-based mode-lockers. These experimental results highlight that 2D b-AsP has great application potential as a novel optical material in ultrafast photonics from near- to mid-infrared regimes.
黑砷磷（b-AsP）作为一种新型二维（2D）材料，填补了黑磷与石墨烯之间的带隙。由于其具有高载流子迁移率、优异的面内各向异性和宽可调带隙等巨大优势，b-AsP在光子学和光电子学领域引起了极大关注。本文通过液相剥离法制备了超薄二维b-AsP纳米材料，并利用紫外-可见-红外和扫描技术对其强宽带线性和非线性吸收进行了表征。实验测得b-AsP的非线性吸收系数和低饱和强度分别为-0.23 cm/GW和3.336 GW/cm。基于密度泛函理论，计算了导带最小值和价带最大值处的部分电荷密度和能带结构，进一步证明了二维b-AsP优异的光学性能。首次将二维b-AsP用作掺铒和掺铥光纤激光器中的新型可饱和吸收体时，锁模孤子脉冲能够在1.5μm和2μm波长处稳定工作。由二维b-AsP产生的激光脉冲比其他基于二维材料的锁模器产生的脉冲具有更高的稳定性，能够抵抗自分裂。这些实验结果表明，二维b-AsP作为一种新型光学材料在近红外到中红外超快光子学领域具有巨大的应用潜力。
