We fabricate an oleic acid capped colloidal lead sulfide quantum dots (PbS QDs) by modified hot-injection method, and then drop them on the end of fiber connector to construct the fiber-based PbS QDs saturable absorber (SA). The modulation depth and saturation intensity of the PbS QDs SA are about 30% and 1.88 MW/cm2, respectively. The strong quantum confinement effect in PbS QDs enables wideband tunability. We get subpicosecond soliton pulses, wavelength-tunable between 1530 nm and 1560 nm, with stable mode-locking, by adjusting the orientations of the polarization controller. These results contribute to study the nonlinear optical properties of zero-dimensional nanomaterials and provide new opportunities for the applications of broadband photoelectronic devices.

中文翻译：

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硫化铅量子点锁模、波长可调孤子光纤激光器

我们通过改进的热注射方法制造了油酸封端的胶体硫化铅量子点（PbS QDs），然后将它们滴在光纤连接器的末端以构建基于光纤的 PbS QDs 可饱和吸收器（SA）。PbS QDs SA 的调制深度和饱和强度分别约为 30% 和 1.88 MW/cm2。PbS QD 中的强量子限制效应使宽带可调性成为可能。通过调整偏振控制器的方向，我们得到亚皮秒孤子脉冲，波长可在 1530 nm 和 1560 nm 之间调谐，具有稳定的锁模。这些结果有助于研究零维纳米材料的非线性光学特性，为宽带光电器件的应用提供新的机遇。