Wavelength Tunable Actively Mode-Locked Tm3+ Doped Fiber Laser with Ghz Repetition Rate

Using an electro-optic lithium niobate phase modulator to synchronise the longitudinal modes in the cavity, a wavelength tunable (1955 - 2045 nm) diode pumped actively mode-locked Thulium doped fiber laser with tunable repetition rate up to GHz level is demonstrated in an all-fiber configuration. We have performed a detailed analysis of the stable mode-locking regimes, including the self mode-locking condition that challenges the harmonic mode-locked operation. We demonstrate a supermode suppression ratio of > 50 dB across the entire wavelength band while maintaining a pulse width and timing jitter of < 50 ps and < 1 ps respectively.