Harith Ahmad, Bilal Nizamani, Mikhail A. Melkumov, Alexey S. Lobanov
A tunable dual-wavelength fiber laser (DWFL) is presented in this work at the 1.3 μm region. The O-band lasing was achieved using bismuth-doped fiber (BDF) as a gain medium, and the in-line six-mode fiber filter (SMFF) was used for DWFL operation. This DWFL was tunable by using the tunable-bandpass filter (TBPF). The DWFL was realized at 1324.6 and 1324.87 nm, achieving signal-to-noise ratios (SNRs) of approximately 59 dB. The dual-wavelength was attained at a spacing of 0.27 nm, which matches the free-spectral range (FSR) generated by the SMFF in the O-band region. By manually adjusting the TBPF, continuous tuning was achieved from 1319.72 nm (λ1) and 1319.99 nm (λ2) to 1328.58 nm (λ1) and 1328.85 nm (λ2), respectively. The O-band region's tuning range was about 9 nm, depending on the gain fiber used within the cavity. These tunable DWFLs at 1.3 μm have potential applications for high-speed wavelength division multiplexing (WDM) systems. © 2025 Elsevier Inc.
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; Prokhorov General Physics Institute of the Russian Academy of Sciences, Dianov Fiber Optics Research Center, 38 Vavilov str., Moscow, 119991, Russian Federation; G.G. Devyatyh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences, 49 Tropinin str., Nizhny Novgorod, 603951, Russian Federation
