Continuous harmonic mode-locked pulsed ultrafast fiber laser based on PtS2 saturable absorber

• Published in: Journal of luminescence 2025-01, Vol.277, p.120958, Article 120958
• Main Authors: Sun, Shixian, He, Yutian, Han, Yu, Zhu, Guangzhao, Shang, Xinxin, Wang, Lezheng, Tang, Yunqi, Li, Keyi, Tan, Hao, Lu, Cheng, Zhang, Wenfei, Wang, Guomei, Bai, Caixun, Li, Zhao, Xu, Nannan, Zhang, Huanian, Fu, Shenggui
• Format: Article
• Language: English
• Subjects: Conventional soliton; Fiber laser; Harmonic mode-locked; PtS2; Saturable absorber
• ISSN: 0022-2313
• DOI: 10.1016/j.jlumin.2024.120958

Saturable absorbers (SAs) play an important role in mode-locked fiber lasers. The search for SAs with excellent modulation properties has become a hot topic in the field of ultrafast photonics. PtS2 is a ideal material for SA due to its suitable band gap and Easily peelable layer structure. We prepared PtS2-SA by liquid-phase exfoliation (LPE) and tapered fiber. Subsequently, we measured the modulation depth of the prepared SA using the two-arm detection method as 6.4 %, and the saturation intensity is 4.5 MW/cm2. By varying the input power in the annular cavity, a conventional solitons (CS) with a center wavelength is 1530.3 nm and a repetition frequency of 6.1 MHz was obtained. Continuing to increase the power, a stable second-fourth orders harmonic mode-locked (HML) was obtained. Our work shows that PtS2-SA has excellent modulation in mode-locked fiber lasers. It also proves that PtS2 has good saturable absorption properties and improves the knowledge of research workers about the performance of PtS2. There is hope in future research work to further exploit the output properties of PtS2. •By performing characterization analyses, we demonstrate that PtS2 have a distinct laminar structure.•The saturable absorber based on PtS2 has a saturable absorption intensity of 4.5 MW/cm2 and a modulation depth of 6.4 %.•Fundamental frequency-locked with a pulse width of 942 fs and 2nd-4th order continuous harmonic mode locking were realized•The experimentally obtained CS and 2nd-4th order continuous HML have high time and power stability.•We demonstrate that the 2D transition metal dichalcogenides PtS2 has excellent saturable absorption properties.