500 fs wideband tunable fiber laser mode-locked by nanotubes

Sub-picosecond tunable ultrafast lasers are important tools for many applications. Here we present an ultrafast tunable fiber laser mode-locked by a nanotube based saturable absorber. The laser outputs ∼500fs pulses over a 33 nm range at 1.5μm. This outperforms the current achievable pulse duration from tunable nanotube mode-locked lasers.

► A high modulation depth (∼10%∼10%) nanotube saturable absorber is fabricated. ► We report a 500-fs wideband tunable fiber laser mode-locked using this nanotube saturable absorber. ► Continuous wavelength tuning (from 1530 nm to 1563 nm) is achieved without the adjustment of any intracavity components. ► This ultrafast wideband-tunable laser only uses single-mode fibers and standard telecom components.