Meng Yafei, Zhu Chunhui, Li Yao, Yuan Xiang, Xiu Faxian, Shi Yi, Xu Yongbing, Wang Fengqiu
Opt Lett. 2018 Apr 1;43(7):1503-1506. doi: 10.1364/OL.43.001503.
In this Letter, the transient nonlinear absorption of three-dimensional (3D) topological Dirac semimetal CdAs thin film was characterized in the near-infrared band. By performing broadband pump-probe measurements, we experimentally proved that molecular beam epitaxy (MBE) grown CdAs exhibits strong and tunable saturable absorption effects across 1-2 μm. By further inserting the CdAs film into the cavities of Tm- and Er-doped fiber lasers, we obtained stable mode-locked operations at 1.96 and 1.56 μm. Our results experimentally establish that CdAs is a promising broadband saturable absorber (SA) for pulsed lasers in the infrared range.
在本信函中，对三维（3D）拓扑狄拉克半金属CdAs薄膜在近红外波段的瞬态非线性吸收进行了表征。通过进行宽带泵浦 - 探测测量，我们通过实验证明，分子束外延（MBE）生长的CdAs在1 - 2μm范围内表现出强烈且可调谐的饱和吸收效应。通过进一步将CdAs薄膜插入掺Tm和掺Er光纤激光器的腔中，我们在1.96μm和1.56μm处获得了稳定的锁模运转。我们的结果通过实验证实，CdAs是用于红外波段脉冲激光器的一种有前景的宽带饱和吸收体（SA）。
