H. Ahmad, M.W.K.M.F. Yasmin, N.A.M. Rusni, I.S. Imaduddin, M.A.M. Lutfi, M.Z. Samion, M.F. Ismail, M.Z.H. Mayzan, Mousa Hussein, S. Sun, Z. Mahmoodin, K. Thambiratnam
In this work, sub-picosecond pulses near the 2.0μm region are obtained from a thulium-doped fiber laser (TDFL) using a combination of a nanoporous carbon (NPC) derived from zeolitic imidazolate framework-8 (ZIF-8) as a physical saturable absorber (SA) together with the naturally occurring nonlinear polarization rotation (NPR) phenomenon in the laser cavity. The NPC, synthesized via direct carbonization at 700∘C, exhibited a high modulation depth of 17.47% with a saturation intensity of 2.8MW/cm2. Initial testing with the standalone NPR configuration generated 1.3ps pulses at 1988.24nm with a 47.3dB signal-to-noise ratio (SNR). The integration of the NPC into the NPR cavity, to form a hybrid SA, resulted in a 10.8% reduction in pulse width to 1.16ps and a shift in the lasing wavelength to 1944.32nm. Furthermore, the hybrid configuration significantly enhanced the operational stability, achieving an improved SNR of 51.1dB. The results indicate that ZIF-8-derived nanoporous carbon is a highly effective nonlinear material for enhancing the performance of ultrafast fiber lasers. © 2026 World Scientific Publishing Company.
Photonics Research Centre, Universiti Malaya, Kuala Lumpur, 50603, Malaysia; Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Malang, Jalan Semarang 5, Malang, 65145, Indonesia; Universiti Kuala Lumpur, British Malaysian Institute (UniKL, BMI), Batu 8, Jalan Sungai Pusu, Selangor, 53100, Malaysia; Centre for Ionics, University Malaya, Department of Physics, Universiti Malaya, Kuala Lumpur, 50603, Malaysia; Ceramic and Amorphous Group (CerAm), Faculty of Applied Sciences and Technology, Pagoh Higher Education Hub, Universiti Tun Hussein Onn Malaysia, Johor, Panchor, 84600, Malaysia; Department of Electrical and Communication Engineering, United Arab Emirates University, Al Ain, United Arab Emirates; Shandong Provincial Key Laboratory of High-end Laser, Manufacturing Technology and Equipment, Qingdao University of Technology (QUT), Qingdao, China; Physics Department, Kulliyyah of Science, International Islamic University of Malaysia, Bandar Indera Mahkota, Pahang, Kuantan, 25300, Malaysia
