Root Mean Square Timing Jitter Research Articles

Intracavity filtering effect in a dual-output linear-cavity all-PM fiber laser mode-locked byNPE.

We have demonstrated a stable and low-noise all-polarization-maintaining (PM) ultrafast erbium-doped fiber laser mode-locked via nonlinear polarization evolution (NPE) in a linear cavity with dual outputs. A detailed design strategy is presented. The all-PM configuration enhances the capability of resistance to environmental fluctuations. Self-starting mode-locking is realized by using a non-reciprocal phase shifter. The dual-output structure offers the intracavity filtering effect, where the reflective port serves as a bandpass spectral filter, significantly improving the transmissive-port optical properties. The laser directly generates ultrashort pulses with a pulse duration of 129fs operating at a fundamental repetition rate of 105.8MHz. The integrated root-mean-square (RMS) relative intensity noise from 10Hz to 10MHz is ∼0.008%, and the integrated RMS timing jitter from 5kHz to 10MHz is ∼36f s. Long-term stability is confirmed in 25h with a RMS power fluctuation of ∼0.10%. Our high-performance fiber laser is a prospective candidate for low-noise applications.

Passive synchronization of femtosecond Er- and Yb-fiber lasers by injection locking

We demonstrated a self-starting passively synchronized Er- and Yb-fiber laser system. Synchronization was implemented by the master-slave configuration where partial output power of the Er-fiber laser was injected into the Yb-fiber laser via a 2-m-long single-mode fiber. The output pulses both were in femtosecond range, and the cavity mismatch tolerance was 160 μm, corresponding to 1267 Hz in frequency domain. The RMS (root mean square) timing jitter between these two lasers was calculated as 14.7 fs (5-kHz bandwidth) in one second.

Measurement of Timing Jitter in Wavelength Tunable Femtosecond Soliton Pulses

We investigated the root mean square (RMS) timing jitter and RMS intensity noise of the wavelength tunable femtosecond soliton pulses using the technique of radio-frequency spectrum analysis. We obtained interesting results that the generated solitons have almost constant RMS timing jitter and RMS intensity noise of approximately 410 fs and 0.03% in the wavelength region of 1600-1750 nm. It is therefore believed that the magnitudes of the jitter and noise are not greatly increased in the process of wavelength tunable soliton pulse generation. The wavelength tunable soliton pulse is confirmed to be stable and useful for practical applications.