Sub-100 kHz repetition rate erbium-doped fiber laser in anomalous dispersion regime

We propose and demonstrate a simple but efficient way to generate low repetition rate pulses in an erbium-doped fiber ring laser by using self-pulsing technique. About 2.25 km long single mode fiber is used to elongate in the cavity, providing large anomalous cavity dispersion in the wavelength region around 1550 nm. Self pulses at a repetition rate of 85.3 kHz with single pulse energy as high as 110 nJ are efficiently obtained on the nanosecond time scale. The experimental results demonstrate that the self-pulse fiber laser operating in the anomalous dispersion regime can also realize high-energy pulses at a very low pulse repetition rate.