Comparison of cavity structures of 200 MHz repetition rate erbium-doped fiber lasers

As an important component of optical frequency combs, mode-locked lasers are also the main source of noise in optical frequency combs. This paper focuses on the effect of the cavity structure of mode-locked lasers on noise performance. At a pump power of 793 mW, the integrated timing jitter within the range of 10 Hz–10 kHz for the ring cavity, σ cavity, and Figure-9 cavity is 216 fs, 307 fs, and 107 fs, respectively, while the integrated relative intensity noise from 1 Hz to 1 MHz is 0.0050%, 0.0029%, and 0.0037%, respectively. The Figure-9 cavity demonstrates superior noise performance, and the σ cavity based on nonlinear polarization rotation also exhibits certain resistance to noise interference.