Versatile multi-wavelength ultrafast fiber laser mode-locked by carbon nanotubes

TLDR

Multi‑wavelength lasers are widely used in fiber telecommunications, pump‑probe measurements, and terahertz generation. The study reports a nanotube‑mode‑locked all‑fiber ultrafast oscillator that emits three tunable wavelengths around 1540–1560 nm. The oscillator uses carbon nanotube mode‑locking and tunable fiber Bragg gratings to adjust the wavelengths. The oscillator delivers ~6‑ps pulses with ~0.5‑nm bandwidth, matches simulations, exhibits <0.04 % amplitude fluctuation, and offers a simple, stable, low‑cost multi‑wavelength ultrafast source for spectroscopy, biomedical research, and telecommunications.

Abstract

Multi-wavelength lasers have widespread applications (e.g. fiber telecommunications, pump-probe measurements, terahertz generation). Here, we report a nanotube-mode-locked all-fiber ultrafast oscillator emitting three wavelengths at the central wavelengths of about 1540, 1550 and 1560 nm, which are tunable by stretching fiber Bragg gratings. The output pulse duration is around 6 ps with a spectral width of ~0.5 nm, agreeing well with the numerical simulations. The triple-laser system is controlled precisely and insensitive to environmental perturbations with <0.04% amplitude fluctuation. Our method provides a simple, stable, low-cost, multi-wavelength ultrafast-pulsed source for spectroscopy, biomedical research and telecommunications.