Performance of Q-switched fiber laser using optically deposited reduced graphene oxide as saturable absorber

• Main Authors: Yap, Yuenkiat, Chong, Wu Yi, Razgaleh, S. A., Huang, Nayming, Ong, Chinkhai, Ahmad, H.
• Format: Article
• Published: Taylor & Francis 2022
• Subjects: QC Physics
• Online Access: http://eprints.um.edu.my/41769/

Graphene is one of the most attractive two-dimensional nanomaterials widely used as saturable absorber for pulsing laser, owing to its unique non-linear optical responses. However, fabrication and integration of graphene saturable absorber into a laser cavity involves complex processes and procedures. Mass production of graphene-based saturable absorbers requires simplification of the fabrication process with minimum material wastage. Reduced graphene oxide, a functionalized graphene, is found to have saturable absorption property as well. Comparatively, it is easier and more cost-effective to produce. On the other hand, optical deposition is a saturable absorber deposition technique that maximizes material utilization. In this work, commercially available reduced graphene oxide in N-methyl-2-pyrrolidone was used to fabricate a saturable absorber device via optical deposition, due to its simplicity and high efficacy. Optical pulse generation via Q-switching were successfully demonstrated with the optically deposited rGO-SA incorporated into a ring erbium-doped fiber laser. Pulse repetition rate of up to similar to 85.0 kHz and pulse durations as short as similar to 2.0 mu s were achieved. Its performance as a saturable absorber in a Q-switched fiber laser is then compared with previous works. Comparatively, optically deposited rGO has a much lower Q-switched threshold and holds huge potential for mass production with maximum material utilization.