Tunable passively Q-switched ultranarrow linewidth erbium-doped fiber laser

• Published in: Results in physics Vol. 16; p. 102949
• Main Authors: Zulkifli, M.Z., Muhammad, F.D., Mohd Azri, M.F., Mohd Yusof, M.K., Hamdan, K.Z., Samsudin, S.A., Yasin, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2020; Elsevier
• Subjects: Doped fiber laser; Passively Q-switched and erbium; Tunable wavelength; Ultra-narrow linewidth; Ultra-narrow linewidth; Doped fiber laser; Tunable wavelength; Passively Q-switched and erbium
• ISSN: 2211-3797; 2211-3797
• DOI: 10.1016/j.rinp.2020.102949

•We demonstrated a passively Q-switched erbium-doped fiber laser with ultranarrow linewidth.•Ultranarrow linewidth laser operation is realized based on spectral filtering effect.•A linewidth value of 17.5 kHz, which may be the narrowest linewidth for a Q-switched fiber laser to the best of our knowledge. A tunable passively Q-switched erbium-doped fiber laser with ultranarrow linewidth is proposed and demonstrated. With the single wall carbon nanotubes (SWCNTs) as the passive Q-switch, the ultranarrow linewidth laser operation is realized based on spectral filtering effect. using an ultranarrow tunable bandpass filter (UNTBF). The Q-switched laser spectrum is tunable from 1525 to 1561 nm, covering a wavelength range of 36 nm. At 1545 nm, the highest repetition rate of ~38 kHz and the lowest pulse width of 1.15 μs are obtained, with the corresponding pulse energy of approximately 0.18nJ. The linewidth measurement using self-heterodyne technique yields a linewidth value of 17.5 kHz, which may be the narrowest linewidth for a Q-switched fiber laser to the best of our knowledge.