H. Ahmad, N.A.M. Rusni, M.Z. Samion
This work demonstrates mode-locked pulses obtained using a polymer-coated cadmium telluride (CdTe) saturable absorber (SA). The arc-shaped fiber was fabricated using a two-step wheel-polishing process, and CdTe SA was drop-casted onto it. Then, it was overcoated with an ultraviolet (UV) cured polymer. This method enhances the fiber’s durability and protects the CdTe SA from air, dust and moisture. The fabricated SA has a saturation intensity of 11.2MW/cm2 and a modulation depth of 19.8%. A stable mode-locked optical spectrum with a center wavelength of 1909.6nm, 3dB bandwidth of 2.9nm, and pulse width of 1.32ps was obtained at a threshold pump power of 398mW. The mode-locked laser has a relatively high signal-noise ratio (SNR) of 64.9dB. Hence, this simple polymer-coating technique enables the application of other volatile compounds as SA for future investigation. © 2026 World Scientific Publishing Company.
Photonics Research Centre, Universiti Malaya, Kuala Lumpur, 50603, Malaysia; Department of Physics, Faculty of Science, 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